MECHATRONICS LEARNING ACTIVITY PACKET - Edl · · 2017-01-02LEARNING ACTIVITY PACKET 1 ... 87-MS1 Pick and Place Feeding Station 87-MS2 Gauging Station 87-MS3 Indexing Station 87-MS4

LEARNINGACTIVITYPACKET

B72001-AA01UEN

AUTOMATIONOPERATIONS

MECHATRONICS

B72001-AA01UEN AUTOMATION OPERATIONSCopyright © 2012 Amatrol, Inc.

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LEARNING ACTIVITY PACKET 1

AUTOMATION OPERATIONS

INTRODUCTIONAs manufacturing industries strive to be successful in a highly competitive

environment, they are increasing their use of more sophisticated automation systems. These systems frequently involve higher speeds, more precision, and integration of IT networks.

Mechatronics is the fi eld of study that produces operators, technicians, and engineers who are qualifi ed to support these sophisticated automation systems. Mechatronics workers must have not only knowledge of the various automation components but also understand systems and integration of these components.

This LAP serves as an introduction to mechatronics systems and teaches the basic concepts of automated machine operation.

ITEMS NEEDEDAmatrol Supplied One or more of the following Mechatronics Stations: 87-MS1 Pick and Place Feeding Station 87-MS2 Gauging Station 87-MS3 Indexing Station 87-MS4 Sorting and Queuing Station 87-MS5 Servo Robotic Assembly Station 87-MS6 Torquing Station 87-MS7 Parts Storage Station 870-PS7313-AAU, 870-PS7314-AAU, or 870-PS7315-AAU Mechatronics Learning System for Siemens S7-300 - one per station 82-900 Siemens Step 7 Programming Software - one per station 72024 Siemens S7-300 Programming Cable

School Supplied Computer with Windows XP Operating System

FIRST EDITION, LAP 1, REV. BAmatrol, AMNET, CIMSOFT, MCL, MINI-CIM, IST, ITC, VEST, and Technovate are trademarks or registered trademarks of Amatrol, Inc. All other brand and product names are trademarks or registered trademarks of their respective companies.Copyright © 2012, 2011 by AMATROL, INC.All rights Reserved. No part of this publication may be reproduced, translated, or transmitted in any form or by any means, electronic, optical, mechanical, or magnetic, including but not limited to photographing, photocopying, recording or any information storage and retrieval system, without written permission of the copyright owner.Amatrol,Inc., 2400 Centennial Blvd., Jeffersonville, IN 47130 USA, Ph 812-288-8285, FAX 812-283-1584 www.amatrol.com


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TABLE OF CONTENTS

SEGMENT 1 INTRODUCTION TO MECHATRONICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4OBJECTIVE 1 Defi ne mechatronicsOBJECTIVE 2 Defi ne a pick and place automation system and give an applicationOBJECTIVE 3 Defi ne a fl exible manufacturing system and give an applicationOBJECTIVE 4 Describe six automated manufacturing processes

SEGMENT 2 CONTROL SYSTEM CONCEPTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21OBJECTIVE 5 Defi ne the basic sequencing control systems modelOBJECTIVE 6 Describe three types of manual discrete logic input devicesOBJECTIVE 7 Describe four types of manual discrete logic output devicesOBJECTIVE 8 Describe nine types of automatic discrete logic input devicesOBJECTIVE 9 Describe two types of automatic discrete logic output devices

SKILL 1 Identify control system component types

SEGMENT 3 MECHATRONICS SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60OBJECTIVE 10 Describe eight mechatronics operator safe dress rulesOBJECTIVE 11 Describe eight mechatronics operator safety rulesOBJECTIVE 12 Describe the operation of an electrical lockout/tagout system

SKILL 2 Perform a lockout/tagout on an electrical systemOBJECTIVE 13 Describe the operation of a pneumatic lockout/tagout system

SKILL 3 Perform a lockout/tagout on a pneumatic system

SEGMENT 4 MACHINE OPERATOR FUNCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77OBJECTIVE 14 Describe the role of a modern automated machine operatorOBJECTIVE 15 Describe the function of a basic operator panelOBJECTIVE 16 Describe the operation of three categories of stop functionsOBJECTIVE 17 Describe how to operate an automated machine

SKILL 4 Power up an automated machine


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SEGMENT 1INTRODUCTION TO MECHATRONICS

OBJECTIVE 1 DEFINE MECHATRONICS

Mechatronics is a fi eld of study that focuses on the integration of mechan-ical, electrical, fl uid, and computer technologies to control machine movements. The term mechatronics was introduced in the early 1970’s by a Japanese fi rm to describe the advent of mechanical equipment (mecha) that uses electronics (tronics) for decision-making functions. Today, the decision-making function is most often performed by a computer.

Figure 1. Mechatronics

MECHATRONICSCAD/CAM CONTROLCIRCUITS

MECHANICS ELECTRONICS

SOFTWARE CONTROL

DIGITALCONTROL

ELECTROMECHANICAL


5

An example of a typical mechatronics application is an assembly line that uses robots and other specialized automated devices to assemble parts. Material is often transported between stations by a conveyor. These systems typically use various types of electrical sensors to monitor machine operation and/or one or more programmable controllers to control machine movements. These control-lers are commonly networked to provide communications between stations and to track the process.

Figure 2. Assembly Line

ROBOT

CNCLATHE

CNCMILL

CONVEYOR

PARTSRACK

VIBRATORYBOWL

FEEDER ASSEMBLYFIXTURE

ROBOT


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OBJECTIVE 2 DEFINE A PICK AND PLACE AUTOMATION SYSTEMAND GIVE AN APPLICATION

Pick and place automation refers to control system applications that involve picking up parts from one location and placing them in another specifi c location.

Figure 3. Pick and Place System


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Pick and place automation systems are typically controlled by a PLC, often using solenoid-operated pneumatic or hydraulic valves to control machine move-ments, although they can also be servo-controlled. A pick and place system is used for material handling applications such as machine loading and unloading as well as sequential assembly operations, where each pick and place device performs one step of a multiple step automated assembly process.

Figure 4. Pick and Place Application

TRANSFER

CONVEYOR B

CONVEYOR A


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OBJECTIVE 3 DEFINE A FLEXIBLE MANUFACTURING SYSTEMAND GIVE AN APPLICATION

While automation systems can be applied to fi xed applications, where they are designed to make a specifi c product, they are increasingly used in fl exible manu-facturing systems. A fl exible manufacturing system, or FMS, consists of a group of automated machines linked by a material handling system and a controller that can be programmed to make a variety of products, product styles, or parts.

Figure 5. Flexible Manufacturing System

One advantage of an FMS is that it reduces cost. The reasons include:• One set of equipment can produce multiple products, so less equipment is needed to produce multiple products• Set-up time is reduced because the system can be reprogrammed to change products instead of being physically retooled• Small batch runs of each product can be produced because product changes can be done by reprogramming, so inventory costs are less

WORK CENTER 1 WORK CENTER 2


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An example of a small FMS is a system that consists of one or two CNC machining stations loaded by a robot and centrally controlled by a programmable controller. The robot automatically loads raw material and unloads fi nished parts for each CNC machine. The PLC can be programmed to signal the robot and CNC machine to change programs automatically to make a variety of products or parts.

Figure 6. Small FMS

PLC CELLCONTROL

ROBOTCONTROL

ROBOT

CNCMACHININGCENTER #2

CNCMACHININGCENTER #1

MATERIALFEED

FINISHED GOODS CONVEYOR


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An example of a large FMS is a system that consists of multiple stations or workstation, linked by a programmable material handling device such as a conveyor. Parts are moved from station to station under control of a central computer, often a PLC, with each station performing a different part of the manufacturing process. The central PLC can be programmed to signal the machines at each station to change their programs to produce different products or product styles. In many cases, each station also has a PLC to communicate with the control PLC and manage functions at that station.

Figure 7. Large FMS

The fi rst applications of fl exible manufacturing systems were in machining of parts for aerospace and automotive industries, but the FMS concept has been applied to virtually all types of manufacturing and manufacturing processes.

FINISHEDPRODUCT

FEED

BASE HOUSINGFEED STATION

#1

#2 #3 #4 #5

BEARING INSERT ROTOR ASSEMBLYREAR HOUSING

ASSEMBLYSCREW

FASTENING

VIBRATIONBOWL

FEEDER

PLC CELLCONTROL


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OBJECTIVE 4 DESCRIBE SIX AUTOMATED MANUFACTURING PROCESSES

Automation is used in many types of manufacturing processes. Some exam-ples of manufacturing processes that are commonly automated include: inventory storage and retrieval, material handling, material processing, fi nishing, assembly (pick and place devices in sequence, welding, gluing, or robotic fastener assembly), and inspection.

Figure 8. Automated Manufacturing Process Flow Chart

Inventory Storage and Retrieval

An automated inventory storage and retrieval system (ASRS) is an automated machine that automatically provides raw material to the manufacturing process and stores fi nished goods. One form of an automated storage and retrieval system is a specialized robot-like device that loads and unloads parts from inventory ware-house racks.

Figure 9. Inventory Storage and Retrieval System

An ASRS can be either centralized or decentralized. The centralized inventory system has all inventory contained in one central location, as in fi gure 9. These systems are often quite large.

RAWMATERIAL

MATERIALREMOVAL FINISHING INSPECTION

TESTINGASSEMBLY FINISHEDPRODUCT


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A decentralized system is where materials are fed to the required process at the workstations. In this type of system, the parts can be fed by parts feeders, such as gravity or vibratory bowl feeders, or placed with robots.

Figure 10. Decentralized Inventory Systems

Material Handling

A fl exible material handling system, or FMH system, consists of one or more machines that automatically move material between workstations. It can be programmed to move material to the specifi c workstations needed by the process for a specifi c part or product. Two types of fl exible material handling systems are programmable conveyors and automated guided vehicles (AGVs).

Figure 11. Material Handling System

FEEDERSYSTEM

PARTS BIN

ASSEMBLY

CONVEYOR


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A conveyor is a device that transports material over specifi c paths using a running belt or chain. A programmable conveyor uses a computer of some type, usually a PLC, to move material to specifi c positions along its length that corre-spond to the locations of workstations where the materials are needed for the manufacturing process.

Figure 12. Conveyor

Two types of programmable conveyors used with an FMS are synchronous and asynchronous. A synchronous conveyor indexes the movement of parts from station to station, making the path and cycle rate the same for each part. An asyn-chronous conveyor allows parts to move independently of each other. Each part can move to its next station when work on the part is completed at its current station.

One type of synchronous conveyor is a pallet transfer conveyor that transports parts on pallets rather than directly on the conveyor. With this type of conveyor, the belt runs continuously and the pallets are stopped at stations by PLC-controlled station positioners.

STATION #1

STATION #4

STATION #2

STATION #3

PALLET


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One advantage of using pallets is that they have the same dimensions, no matter what material is on the pallet, so they can be guided in the same way and accurately stopped at each station. This allows the robots or other devices at each workstation to be programmed to move to known points at the pallet each time to pick up the part from the pallet or do work on the pallet.

Figure 13. Pallet Transfer Conveyor


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An automatic guided vehicle, or AGV, is an unmanned vehicle that transports materials between workstations by following a programmed path. This path is often defi ned by an electrical wire laid into the fl oor but other methods are used as well. Most AGV’s have an on-board computer that directly controls the operation of the vehicle. Some vehicles are pre-programmed with a specifi c path and others communicate with a remote computer via radio frequency (RF) communications to get instructions for the destination of each material.

Figure 14. AGV System

AGV’s are common substitutes for a conveyor when the distance between workstations is very large or the conveyor structure blocks the movement of people or other processes.


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Material Processing

Material processing workstations usually consist of one or more computer numerical controlled (CNC) machines that perform a specialized material process and a robot to load and unload the workpiece from each machine. Material processes include: machining, casting, and molding.

Machining includes material removal such as milling, turning, and grinding. Other material removal processes can include laser cutting, water jet cutting, EDM, and routing.

Figure 15. Material Processing


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Finishing

Finishing processes improve the appearance or provide a protective coating to a part or product. Examples include polishing, grinding, trimming, painting, anod-izing, and chrome plating.

Finishing workstations commonly use robots to directly perform the fi nishing task by guiding the movement of a fi nishing device of some type such as a paint gun or polishing tool. Auto body painting is one of the most common examples of an FMS fi nishing application.

Figure 16. Finishing Process


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Assembly

Assembly is the process of joining two or more separate parts. Assembly processes include mechanical fastening operations that use screws, nuts, rivets, or adhesives. Also included are processes such as welding, brazing, soldering, and gluing.

Automated assembly workstations use robots or PLC-controlled pick and place devices to assemble parts.

Figure 17. Assembly Process

FEEDERSYSTEM

PARTS BIN

ASSEMBLY

CONVEYOR


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Inspection

Inspection is the process of determining if the part or product meets one or more design specifi cations. Common inspection processes include measurement of part dimensions by a gauging device of some type, vision inspection of product assemblies, or functional testing of product operation.

Inspection workstations load parts into specialized inspection machines or the inspection device may be designed to test the device directly on the mate-rial handling system. Electronic circuit boards are commonly inspected by vision systems to make sure that all components are assembled.

Figure 18. Inspection Station


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SEGMENT 1 SELF REVIEW

1. The decision making function of mechatronics is performed mostly by _____________.

2. Pick and place automation systems are controlled by a ______________.

3. One reason an FMS can reduce cost is because one set of equipment can produce _____________.

4. Automated storage and retrieval systems provide ___________ to the manufacturing process and store fi nished goods.

5. A decentralized ASRS feeds the materials directly to the _____________.

6. Two types of ______________ are programmable conveyors and automated guided vehicles.

7. A(n) ___________ conveyor allows parts to move independently of each other.

8. An AGV transports materials between workstations by following a ____________.

9. Material processes include machining, casting, and ____________.

10. Assembly processes include mechanical fastening, welding, brazing, soldering, and ____________.


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SEGMENT 2CONTROL SYSTEM CONCEPTS

OBJECTIVE 5 DEFINE THE BASIC SEQUENCING CONTROLSYSTEMS MODEL

While automation systems can vary widely in design and purpose, they gener-ally have a controller that is programmed or designed to make the machine compo-nents perform a series of actions or steps. This is called the machine sequence, and understanding this sequence is a key part of understanding the machine’s operation.

To perform a machine sequence, the controller is connected to various input and output devices and then programmed with logic so it turns certain outputs on or off in a sequence in response to receiving a specifi c sequence of input signals. Each step of a control system sequence starts with an input signal, or signals, the logic then decides what outputs to turn on or off, and the outputs turn on or off to make the machine step take place.

Figure 19. Basic Control System Sequence Model

LIMIT SWITCHSIGNAL

PLCPROGRAM

LOGIC

MOTORSTARTS

INPUT LOGIC OUTPUT


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To create a sequence of steps, the input devices are physically arranged on the machine so the completion of one step’s action triggers an input device to signal the controller to start the next step. The multi-step sequence is represented by a series of basic sequence models where the output of the previous step triggers an input device to make the next step take place. For example, consider the clamp and drill sequence example shown in fi gure 20, which consists of two actuators performing a 4-step sequence. The sequence is:

Step 1: Clamp cylinder extend

Step 2: Drill cylinder extend

Step 3: Drill cylinder retract

Step 4: Clamp cylinder retract

Figure 20. Clamp and Drill Application

The logic diagram for this clamp and drill sequence is shown in fi gure 21. Here you can see which input triggers a particular output in the sequence.

When the operator presses PB1 to start the sequence, the clamp cylinder extends. When the clamp cylinder is extended, it actuates LS3, which starts step 2 of the sequence, drill cylinder extend.

START

STOP

LS1

LS2

DRILL

PART CLAMPCYLINDER

PLC MOUNTEDINSIDE

LS3 LS4

DRILLCYLINDER

PB1


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When the drill cylinder becomes extended, it actuates LS2, which starts step 3, drill cylinder retract. In this case, the controller turns off an output to cause this step to occur.

When the drill cylinder becomes retracted, it actuates LS1, which starts step 4, clamp cylinder retract. Again, the controller turns off an output to cause this step to occur.

When the clamp cylinder is retracted, it actuates LS4, which stops the sequence.

Figure 21. Clamp and Drill Cylinder Sequence

INPUTS LOGIC OUTPUTS

CLAMP CYLINDEREXTENDS

DRILL CYLINDEREXTENDS

DRILL CYLINDERRETRACTS

PB1ON/OFF

LS3ON

LS2ON

PLCLOGIC

PLCLOGIC

PLCLOGIC

SOL 2AON

SOL 1AON

1

STEP

2

3

CLAMP CYLINDERRETRACTS

LSON

1 PLCLOGIC

SOL 2AOFF

CYCLESTOPS

LS4ON

PLCLOGIC

NOOUTPUTCHANGE

4

5

SOL 1AOFF

OPERATORPRESSES PB1

CLAMP CYLINDEREXTENDED

DRILL CYLINDEREXTENDED

DRILL CYLINDERRETRACTED

CLAMP CYLINDERRETRACTED


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OBJECTIVE 6 DESCRIBE THREE TYPES OF MANUAL DISCRETE LOGIC INPUT DEVICES

Most automated machines have a control panel that allows the operator to control and monitor the basic functions of the machine such as start, stop, and mode select. The most basic type of control panel consists of pushbuttons, selector switches of various types, and BCD (binary coded decimal) thumbwheels wired to the discrete input terminals of the PLC.

Figure 22. Control Panel


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Pushbutton Switches

Pushbutton switches are used in control systems to manually send input signals to the controller to cause it to perform functions such as starting and stopping the machine. Pushbutton switches can be either momentary or maintained. A momen-tary switch contains a spring that causes the operator to return to its original posi-tion and the contacts to return to their normal state once the person releases the button. A maintained pushbutton stays pushed in and holds the contacts in the actuated state after the person releases the button. To de-actuate the contacts, the person must pull out the button or push it a second time.

Pushbuttons are available with a variety of operator types and colors to provide easy operation and identifi cation. The mushroom head pushbutton is designed so the operator can quickly locate and press the button. This is reserved for functions such as Emergency Stop. The extended button extends beyond the body of the operator so that the color of this operator can be easily seen from all angles. The fl ush button is guarded by the button body to prevent accidental actuation. This button is often used as a start button.

Figure 23. Pushbuttons

MUSHROOMHEAD

FLUSHBUTTON

EXTENDEDBUTTON


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Selector Switches

A selector switch is a type of manual switch that operates its contacts by rotating the operator into a position. It is used most often to change the mode of operation of a machine, such as On/Off, Manual/Automatic, Run/Jog, and Forward/Reverse. Common selector switches can have either two or three posi-tions, and either momentary or maintained contacts. The maintained types stay in the position set by the operator, while the spring return, or momentary types, return to the starting position once it is released.

Figure 24. Selector Switches

SELECTORSWITCHES


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BCD Thumbwheel Switch

A BCD thumbwheel switch provides multiple inputs to a controller or PLC to enable the operator to input data such as a time delay or production count.

The BCD thumbwheel switch consists of four parallel switches controlled by the thumbwheel. When the operator dials in a decimal number (0-9) on the display, the BCD thumbwheel sets each of its switches either on or off to form a BCD value corresponding to the decimal value displayed. For example, dialing in a decimal value of 3 would cause the switch to output 0011BCD on the four data lines.

Figure 25. BCD Thumbwheel

A BCD thumbwheel switch is typically wired to four adjacent discrete inputs on an input module of a PLC. The PLC has an instruction that can read the four inputs as a group and create a decimal number.

0

1

2

3

4

5

6

7

0

1

2

3

4

5

6

7

000011000

00

0001

0

MOSTSIGNIFICANT

DIGIT

LEASTSIGNIFICANT

DIGIT

GROUP OFFOUR BCD

THUMBWHEELSWITCHES

16 POINTINPUT

MODULE

+24V

THUMBWHEEL


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OBJECTIVE 7 DESCRIBE FOUR TYPES OF MANUAL DISCRETE LOGIC OUTPUT DEVICES

In addition to manual input devices most operator panels include manual output devices as well. These manual output devices include indicator lamps of various types, audible alarms, message displays, and LED displays to help the operator monitor the status of the machine.

Figure 26. Operator Panel

Indicator Lamps

Indicator lamps are used by electrical control systems to tell the operator at a glance the operating status of the machine. They have many uses, including indi-cating that power to a machine is on, a cycle has begun or ended, and a sensor has sensed an input.

Figure 27. Indicator Lamps


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Audible Alarms

Audible alarms are used to alert the operator to an event that needs immediate attention. An alarm may turn on if a part or feeder is jammed or if a liquid tempera-ture goes beyond the range limits.

Figure 28. Alarm

Message Displays

Message displays are used to display information to the operator and main-tenance personnel about the status of a machine or process. They store prepro-grammed messages that are displayed when the unit receives a signal from a programmable controller. Messages may be displayed to tell the operator what process is being performed on a part, the temperature of an oven, or that a piece of equipment has faulted.

Figure 29. Message Display - “Siemens AG 2006, All rights reserved”t


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LED Display

An LED display is an output device that enables a machine operator to view the value stored in a PLC memory location without the use of a programming terminal. This enables the operator to view data such as the elapsed time for a time delay or a count representing the current production level.

Figure 30. 4-Digit LED Display

Each decimal digit of an LED display is controlled by four data lines that are wired to four output terminals of a PLC output module. The digit displayed by each LED display is the decimal form of the BCD value the display receives from the PLC output module terminals. The operation of an LED display is the counter-part to the BCD thumbwheel switch.

0

1

2

3

4

5

6

7

0

1

2

3

4

5

6

7

000000000

00

0111

1

MOSTSIGNIFICANT

DIGIT

LEASTSIGNIFICANT

DIGIT

4 DIGIT LEDOUTPUT DISPLAY

STATUS OFDATA LINES

16 POINTOUTPUTMODULE


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OBJECTIVE 8 DESCRIBE NINE TYPES OF AUTOMATIC DISCRETE LOGIC INPUT DEVICES

Sensors that are used to detect actuator position are called automatic input devices because the machine automatically triggers them. Many of these sensors are discrete types, which output an on or off signal. Eight types commonly-used on/off type sensors are:

• Limit switch• Magnetic reed switch• Capacitive proximity sensor• Inductive proximity sensor• Photoelectric proximity sensor• Infrared proximity sensor• Fiber optic proximity sensor• Hall-effect sensor• Giant magnetoresistive sensors

Limit Switch

A limit switch is an input switch used on automatic machines to sense the posi-tion of a machine member by mechanical means and convert the position into an electrical signal. This electrical signal is used by the control logic circuit to start a new step in the machine sequence. Limit switches are commonly used because they are low cost. However, since they use moving parts they do not last as long as electronic sensors.

Figure 31. Limit Switches


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Magnetic Reed Switch

A magnetic reed switch is a fast-operating, electrical switch with normally open contacts that close when they encounter a magnetic fi eld. They can only sense objects that generate a magnetic fi eld. Magnetic reed switches are often used on aluminum cylinders in pneumatic applications to detect when the cylinder is at the end of its stroke. The cylinder piston is equipped with a magnet to trigger the switch. Magnetic reed switches are highly accurate, low cost, and long lasting. In light use, they can be used for billions of cycles.

Figure 32. Magnetic Reed Switch

Capacitive Proximity Sensor

A capacitive proximity sensor uses the principle of capacitance to sense the presence of an object. It creates an electrostatic fi eld that is used to sense when a part comes into range and turn on a transistor output. A capacitive proximity sensor can sense both metal and non-metallic objects.

Figure 33. Capacitive Proximity Sensor


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Inductive Proximity Sensor

An inductive proximity sensor uses the principle of induction to sense the pres-ence of a metallic object. It creates a magnetic fi eld that is used to sense when a metal part comes into range and turn on a transistor output. Ferrous targets that contain iron, like steel, can be detected at greater distances than nonferrous targets such as aluminum. Inductive sensors are less expensive than capacitive sensors, so they are preferred if the object being detected is metal.

Figure 34. Inductive Proximity Sensor

Photoelectric Proximity Sensor

A photoelectric sensor energizes its output when it senses light. The sensor is a solid-state device that uses a principle called photoconduction to operate. Photo-conduction is the ability of a material to conduct electrical current when struck by light. Photoelectric sensors have a much greater sensing distance than other types of electronic sensors such as capacitive or inductive sensors.

Figure 35. Photoelectric Sensor


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Infrared Proximity Sensor

An infrared proximity sensor is a photoelectric sensor that outputs infrared light rather than visible light. They are higher-powered photoelectric sensors and are suited for areas that contain a high amount of ambient light, which can affect visible light sensors.

Figure 36. Infrared Sensor

Fiber Optic Proximity Sensor

A fi ber optic sensor is a photoelectric sensor that uses fi ber optic fi laments attached to the photoelectric sensor to send and receive the light. The cables attached to the photoelectric sensor guide the light through the fi ber optic fi laments and out through the sensing head, while the cables attached to the receiver returns the light. Fiber optic sensors are used in tight sensing locations, extreme (highly corrosive or high moisture) or high temperature environments, and areas of high vibration and shock.

Figure 37. Fiber Optic Sensor

SENSORHEAD

SIGNALCONDITIONER


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Hall-Effect Sensor

A Hall-effect sensor energizes its output when a magnetic fi eld is sensed, just like a magnetic reed switch. The sensor is a solid-state device that operates on a principle called transduction, the Hall-effect. The Hall-effect is the ability of a conductive material to develop a voltage potential at right angles to current fl ow when subjected to magnetic fi elds. Hall-effect sensors are used instead of magnetic reed switches in operations where fast response time is needed. Because they are solid-state, Hall-effect switches react faster than reed switches.

Figure 38. Hall-Effect Sensor


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Giant Magnetoresistive Sensor

A giant magnetoresistive (GMR) sensor is a magnetic sensor that responds mainly to the magnetic fi eld orientation and direction rather than the magnetic fi eld strength. This sensor is a solid-state device that operates on a principle called the giant magnetoresistive effect. The giant magnetoresistive effect is based on very thin layers of iron and other magnetic metals with spacer layers of non-magnetic metal stacked between them. One layer of the magnetic metal is pinned in one direction through the use of a layer with a strong antiferromagnet. When a weak magnetic fi eld passes under the sensor, the magnetic orientation in the unpinned magnetic layer rotates relative to the pinned layer, which generates a change in the electrical resistance due to the GMR effect.

GMR sensors are very useful in non-contact position registration applications, such as distance, speed, and rotation measurements. These sensors are more sensi-tive than regular magnetic reed switches and therefore can be used in applications where magnetic reed switches cannot.

Figure 39. Giant Magnetoresistive Sensor


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OBJECTIVE 9 DESCRIBE TWO TYPES OF AUTOMATIC DISCRETE LOGIC OUTPUT DEVICES

To operate an automated machine the controller must be connected to output devices that control the fl ow of power to the actuators. In non-servo fl uid power systems, these output devices are typically solenoid-operated directional control valves (DCVs). In electric motor applications, the output device is a motor starter.

Directional Control Valves

DCV’s control the motion of the actuators by controlling the direction of the fl uid fl ow. DCV’s are often operated by electric solenoids, which receive signals from the controller. DCV’s are used to control cylinders, motors, and rotary actuators.

Figure 40. Directional Control Valve


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DCV’s move in two directions. This can be accomplished by using one sole-noid and a return spring, two solenoids alone, or two solenoids with return springs.

As shown in fi gure 41, when the controller receives an input signal, it turns on one of its outputs, which turns on the solenoid. The valve shifts and provides fl uid fl ow to power the actuator.

Figure 41. Activation of Directional Control Valve

1 1

1 2

1 3

1 4

1 5

1 6

1 7

1 8

1 9

2 0

1

2

3

4

5

6

7

8

9

1 0ACTUATOR

RETURNSPRING

SOLENOIDENERGIZED FROM AIR COMPRESSOR

01234567

01234567

+

-

24VDC

OUTPUTS


39

Electric Motor Starters

A magnetic motor starter functions as a large relay to start and stop a motor by opening and closing the power lines to the motor. A magnetic motor starter also includes overload protection, which stops the motor if it draws excessive power. Motor starters are used to control constant speed AC and DC motors.

Figure 42. Magnetic Motor Starter


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A PLC operates a motor starter by turning on one of its outputs. This output energizes a solenoid in the motor starter, which closes the starter’s contacts and allows electrical power to fl ow through to the motor.

Figure 43. Activation of Magnetic Motor Starter

1 1

1 2

1 3

1 4

1 5

1 6

1 7

1 8

1 9

2 0

1

2

3

4

5

6

7

8

9

1 0

L1

L2

L3

SOLENOID

CONTACTOR

MOTORSTARTER

01234567

1

10

2

3

4

5

6

7

8

9

11

20

12

13

14

15

16

17

18

19

01234567

+

-

24VDC

MOTOR

OUTPUTS


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SKILL 1 IDENTIFY CONTROL SYSTEM COMPONENT TYPES

Procedure Overview

In this procedure, you will familiarize yourself with the functions of the various stations that make up the 870 Mechatronics learning system and its components. Your organization may have any number of the mechatronics stations. Review the ones that you have available to you.

1. Locate the 870 Mechatronics System shown in fi gure 44. This system is designed to assemble a family of pneumatic directional control

valves.

Figure 44. 870 Mechatronics System


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Figure 45 shows the model number and description of each station.

MODEL NAME DESCRIPTION

87-MS1 Pick and Place Feeding Station

87-MS2 Gauging Station

87-MS3 Indexing Station

87-MS4 Sorting and Queuing Station

87-MS5 Servo Robotic Assembly Station

87-MS6 Torquing Station

87-MS7 Parts Storage Station

Figure 45. Mechatronics Stations

2. Perform the following substeps to familiarize yourself with station 1, which is the Model 87-MS1 Pick and Place Feeding station.

This station uses a powered parts feeder to supply parts to a 2-axis pick and place manipulator. The pick and place manipulator picks up the parts from the feeder and places them in a bin or onto the next station, if attached.

Figure 46. Pick and Place Feeding Station

A. Locate the Powered Parts Feeder, shown in fi gure 46.

This feeder uses a gravity parts feeder with a powered cylinder that pushes parts out to the pick up location.

POWEREDPARTS FEEDER

2-AXISPICK AND PLACE

MANIPULATOR

PARTSBIN

ELECTRO-PNEUMATIC

VALVEMANIFOLD


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B. Locate the 2-Axis Pick and Place manipulator, shown in fi gure 46.

This pick and place unit uses a rodless cylinder and a cylinder with guide shafts controlled by solenoid operated DCV’s and a vacuum gripper to pick up parts and place them in a different location.

C. Locate the Electro-Pneumatic Valve Manifold, shown in fi gure 46.

This valve manifold includes a 4-station manifold with one single-solenoid, 2-position DCV, and three double-solenoid, 2-position detent DCV’s, all with manual overrides.

D. Locate the Parts Bin, shown in fi gure 46.

This bin is used to hold the parts from the pick and place robot when Station 1 is not connected to other stations.

E. Locate the Parts Set.

The parts set includes eight acrylic valve bodies for use with this and subsequent stations.

3. Perform the following substeps to familiarize yourself with station 2, which is the Model 87-MS2 Gauging station.

This station inspects valve bodies for correct port locations and for correct body thickness. If the ports are not positioned correctly, missing, or the body is not the correct height, the station will reject the part to a reject bin. Otherwise, it will push the part into a parts bin or on to the next station, if attached.

Figure 47. Gauging Station

PROXIMITYGAUGINGMODULE

PART TRANSFERMODULE

ULTRASONICMEASUREMENT

MODULE

TRAVERSESHUTTLE

PART REJECTMODULE

ELECTRO-PNEUMATIC

VALVEMANIFOLD


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A. Locate the Traverse Shuttle, shown in fi gure 47.

The traverse shuttle uses a DC motor controlled by a reversing motor starter. It also has a clutch to drive a synchronous belt that is connected to a precision ball screw. A carriage is mounted onto the traverse to hold and carry the valve body.

B. Locate the Ultrasonic Measurement Module, shown in fi gure 47.

The ultrasonic measurement module uses an ultrasonic sensor mounted on a stand over the traverse to measure the height of the valve body.

C. Locate the Proximity Gauging Module, shown in fi gure 47.

The proximity gauging module uses a diffused mode infrared proximity sensor to detect the presence of a port in the valve body. If the port is missing or if the valve body is oriented incorrectly and the port is not in the specifi ed location, the valve body is rejected.

D. Locate the Part Transfer Module, shown in fi gure 47.

The part transfer module uses two pneumatic cylinders to move the valve body. One vertical, single-acting cylinder located under the carriage pushes the part up and out of the carriage recess so that the part reject cylinder or part transfer cylinder can push the part off the carriage.

The part transfer cylinder uses a cylinder with magnetic reed switches for location sensing. This cylinder pushes the valve body into a bin or onto the next station, if attached.

E. Locate the Part Reject Module, shown in fi gure 47.

The part reject module uses the same kind of cylinder as the part transfer module, but it pushes the valve bodies into a reject bin where they have to be manually removed.

F. Locate the Electro-Pneumatic Valve Manifold, shown in fi gure 47.

This valve manifold includes a 3-station manifold with two single-sole-noid, 2-position DCV’s, and one double-solenoid, 2-position detented DCV, all with manual overrides.

G. Locate the Parts Set.

The parts set includes four acrylic reject valve bodies for use with this and subsequent stations. It also includes two aluminum gauge blocks used in programming the ultrasonic sensor.


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4. Perform the following substeps to familiarize yourself with station 3, which is the Model 87-MS3 Indexing station.

This station checks the orientation of the valve body. If it is in the correct orientation, it moves the valve body to a part transfer module, where it is moved to a bin or to the next station. If the valve body is not in the correct orientation, it is indexed to the pick and place manipulator, which puts it into the correct orientation and then it is indexed to the part transfer module for movement to a bin or to the next station.

Figure 48. Indexing Station

A. Locate the 8-Station Rotary Index Table, shown in fi gure 48.

The rotary index table has a round 8-station table mounted to a stepper motor with on-board intelligent control. This allows the motor to be stopped at specifi c positions. The table uses two capacitive proximity sensors to sense the presence of a valve body, one at the initial location and one at the orientation location.

B. Locate the Pick and Place Pneumatic Manipulator, shown in fi gure 48.

The pick and place manipulator uses a curvilinear 2-point gripper and a rotary actuator to orient the valve bodies. When a valve body arrives at the orientation location, the manipulator lowers and the gripper grips the part. The manipulator then moves up, rotates 180°, and lowers again to place the part back on the index table.

ROTARYINDEX TABLE

FIBER OPTICGAUGING MODULE

PICK AND PLACEMANIPULATOR

PARTTRANSFER

MODULE

ELECTRO-PNEUMATIC

VALVEMANIFOLD


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C. Locate the Fiber Optic Gauging Module, shown in fi gure 48.

The fi ber optic gauging module uses a fi ber optic photoelectric sensor to locate the presence of a port in the valve body. This tells the system if the part has to be reoriented or if it can be moved on to the part transfer module.

D. Locate the Part Transfer Module, shown in fi gure 48.

The part transfer module uses a pneumatic cylinder with magnetic reed switches for location sensing. When the system indexes a valve body to the part transfer module, the cylinder extends and pushes the part into a bin or onto the next station, if attached.

E. Locate the Electro-Pneumatic Valve Manifold, shown in fi gure 48.

This valve manifold includes a 4-station manifold with one single-solenoid, 2-position DCV, and three double-solenoid, 2-position detent DCV’s, all with manual overrides.

5. Perform the following substeps to familiarize yourself with station 4, which is the Model 87-MS4 Sorting and Queuing station.

This station sorts the aluminum valve bodies from the acrylic bodies. When the valve body is placed on the end of the conveyor, a photoelectric sensor detects the part and an inductive sensor detects if it is aluminum. The parts are sorted according to the material, pushing one material type to the far side of the conveyor while leaving the other material type on the near side. The valve bodies then continue down the conveyor. The last section of the conveyor has a sorter/buffer to keep the parts separated. The valve bodies stay on the conveyor until picked up by the next station or manually removed.

Figure 49. Sorting and Queuing Station

PARTSORTINGMODULE

BELT CONVEYORMODULE

PROXIMITYSENSINGMODULE

BUFFERMODULE

ELECTRO-PNEUMATIC

VALVEMANIFOLD


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A. Locate the Belt Conveyor Module, shown in fi gure 49.

The belt conveyor is a fi xed speed conveyor, which is powered by an elec-tric motor. At the beginning of the conveyor, a photoelectric switch is used to sense when there is a part on the conveyor.

B. Locate the Part Sorting Module, shown in fi gure 49.

The part sorting module uses an inductive sensor along with the capaci-tive proximity sensor at the beginning of the conveyor to detect if the valve body is aluminum. If both sensors see the valve body, indicating it is metal, a cylinder with a push bar extends to push the metal body to the other side of the conveyor where it will continue down the conveyor. If the inductive sensor does not sense the part, but the capacitive proximity sensor does, indicating the part is not metal, it is sent down the near side of the conveyor.

C. Locate the Buffer Modules, shown in fi gure 49.

The two buffer modules consist of formed sheet steel channels to separate the acrylic parts from the aluminum parts. Because the valve bodies ride on the conveyor they would stack up at the end of the conveyor, making it diffi cult for any automated system to remove them. To prevent this, each channel has a restraining arm mechanism that is controlled by a single-acting cylinder. When the arm moves to let a valve body move to the end of the conveyor, the back of the arm rotates and grips the next body in line to prevent it from moving. Once the fi rst part clears the area, the arm snaps back into position to allow the next part to move into the pickup position.

D. Locate the Proximity Sensing Module, shown in fi gure 49.

The proximity sensing module uses a retro-refl ective proximity sensor to detect valve bodies in the pick up location at the buffering station.

E. Locate the Electro-Pneumatic Valve Manifold, shown in fi gure 49.

This valve manifold includes a 3-station manifold with one single-sole-noid, 2-position DCV, and two double-solenoid, 2-position detent DCV’s, all with manual overrides.

F. Locate the Parts Set.

The parts set includes eight aluminum valve bodies for use with this and subsequent stations. This set adds to the acrylic parts set supplied with station 1.


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6. Perform the following substeps to familiarize yourself with station 5, which is the Model 87-MS5 Servo Robotic Assembly station.

This station assembles the valve by installing the spool, screw, spring, and knob. It uses a servo robot to assist in placement and orientation of the valve body. The valve is assembled in two stages. In the position next to the spool insertion module, the spool and screw are inserted. After this step takes place, the valve is moved to the second assembly position where the spring and knob are attached. The robot used with the assembly station will be a Pegasus or a Saturn.

Figure 50. Servo Robotic Assembly Station

A. Locate the Valve Clamp Modules, shown in fi gure 50.

The valve clamp modules, one located at the spool insertion module and one at the spring/knob assembly module, use pneumatic cylinders to hold the valve bodies in place during assembly. These cylinders each have one magnetic reed switch to tell the system when the part is clamped.

B. Locate the Spool Feeder Module, shown in fi gure 50.

The spool feeder module is a gravity feeder that stores both 4-way and 3-way spools. The feeder is attached to a cylinder that positions the feeder to its extended position or retracted position to allow the installation of the desired spool into the valve body.

SCREWFEEDER

VALVE CLAMPMODULES SPRING / KNOB

ASSEMBLYFEEDER

SPRING / KNOBASSEMBLYMODULE

ELECTRO-PNEUMATIC

VALVEMANIFOLD

SCREWINSERTION

MODULE

PART INDEXMODULE

SPOOL FEEDERMODULE


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C. Locate the Spool Insertion Module, shown in fi gure 50.

The spool insertion module uses a pneumatic cylinder with magnetic reed location switches on either end. On the end of the cylinder rod is a tapered tip that is designed to push through the bottom of the spool feeder and push the spool into the valve body. Once a spool is pushed out of the feeder, the remaining spools in the magazine drop down on the cylinder rod while it is extended. The tapered shape of the tip allows the cylinder to retract without catching the edge of the next spool on the retract stroke.

D. Locate the Screw Feeder, shown in fi gure 50.

The screw feeder is a pneumatic tube feeder that uses compressed air to push the screws to the insertion location. This feeder’s air supply has a its own regulator because it only requires approximately 10 psi to feed the screws. It also has a parts presence sensor that tells you if the feeder is empty or not. Note that the parts presence sensor detects the bolt that is the third one back from the one ready for insertion.

E. Locate the Screw Insertion Module, shown in fi gure 50.

The screw insertion module includes three pneumatic cylinders. One cylinder is used as a part restraint, which keeps the parts from entering the assembly location at the wrong time. The other two cylinders are used to line up the part for assembly. The screw feeder holds a screw ready and when the spool is inserted, it is actually extended over the end of the screw, which aids in the screw insertion.

Once the screw is inserted, the part is indexed to the second assembly posi-tion. During this travel, the assembly goes through a fi xture that pushes the screw/spool assembly further into the valve body.

F. Locate the Part Index Module, shown in fi gure 50.

The part index module is a rodless cylinder that is mounted underneath the assembly work surface. Attached to it and extending up through the work surface is a tab that is used to push the part from one assembly module to the other. This cylinder has end of travel limit switches attached to each end.

G. Locate the Spring/Knob Assembly Feeder, shown in fi gure 50.

The spring/knob assembly feeder is a gravity feeder with a small, move-able stop at the bottom. This feeder holds the assembled spring and knob in the knob down orientation. It is designed to allow the robot to remove the assembly and place it in the assembly module.


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H. Locate the Spring/Knob Assembly Module, shown in fi gure 50.

In the spring/knob assembly module, the part is clamped into place with a valve clamp. The robot positions the spring/knob assembly that it removed from the feeder and places it into an alignment groove on the assembly module’s work surface. A pneumatic cylinder then extends to push the spring/knob assembly to contact the valve body.

When the cylinder starts to extend, an electric motor on the opposite side of the valve body turns on. As the spring/knob assembly contacts the bolt, it pushes the bolt partly out of the valve body. The head of the bolt makes contact with a rubber tip mounted on the end of the motor shaft. This turns the bolt, which engages the threads into the knob. This will prevent the assembly from coming apart when it is moved to the next station.

The motor turns off after a (programmed) time and the insertion cylinder retracts. The clamp cylinder retracts. The robot then picks up and orients the assembly and places it in a bin or into the next station, if attached.

I. Locate the Electro-Pneumatic Valve Manifold, shown in fi gure 50.

This valve manifold includes a 7-station manifold with six single-sole-noid, 2-position DCV’s, and one double-solenoid, 2-position detent DCV, all with manual overrides.

J. Locate the Parts Set.

The parts set includes eight 3-way valve spools, eight 4-way valve spools, eight manual operators (knobs), eight bolts, and eight return springs for use with this and subsequent stations. It adds to the parts sets supplied with stations 1 and 4.


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7. Perform the following substeps to familiarize yourself with station 6, which is the model 87-MS6 Torquing station.

This station tightens the screw in the knob to the correct torque. The part is then transferred to the end of the station on an electric belt-drive traverse. Once at the end of the traverse, the part is manually picked up by the next station’s manipulator, if attached, and moved to the next station.

Figure 51. Torquing Station

A. Locate the Screw Torque Module, shown in fi gure 51.

The screw torque module uses an electric motor with an adjustable clutch to torque the screw to the correct amount. The motor has a screwdriver attachment mounted on the shaft. A pulse width modulator allows the motor speed to be varied.

B. Locate the Knob Clamp Module, shown in fi gure 51.

The knob clamp module is located on the other side of the valve body. A pneumatic cylinder extends and a curvilinear gripper grips the valve knob. An inductive sensor detects when the part is gripped. The gripper holds the knob stationary while th e screw is tightened to the correct torque.

C. Locate the Electric Traverse Module, shown in fi gure 51.

The electric traverse module uses a synchronous belt drive powered by a reversible electric motor with a thermal overload and an adjustable clutch. The traverse has end-of-travel limit switches on each end.

D. Locate the Electro-Pneumatic Valve Manifold, shown in fi gure 51.

This valve manifold includes a 2-station manifold with two single-sole-noid, 2-position DCV’s with manual overrides.

SCREWTORQUEMODULE

KNOBCLAMP

MODULE

ELECTRICTRAVERSEMODULE

ELECTRO-PNEUMATIC

VALVEMANIFOLD


52

8. Perform the following substeps to familiarize yourself with station 7, which is the model 87-MS7 Parts Storage station.

This station uses a pneumatic manipulator to sort parts according to material and spool type. It has a divided gravity feed parts tray to hold the parts.

A. Locate the Programmable Position Pneumatic Manipulator, shown in fi gure 52.

The programmable position pneumatic manipulator uses a pneumatic rodless cylinder with a brake and infrared sensors for positioning. This manipulator uses a curvilinear 2-point gripper to remove parts from the previous station and sort them according to its program. The infrared sensors are used with tabs fastened onto the horizontal axis to sense location.

Figure 52. Parts Storage Station

B. Locate the 4-Channel Parts Storage Module, shown in fi gure 52.

The parts storage module is sheet steel mounted at an angle and divided into four sections for the four different types of parts.

C. Locate the Electro-Pneumatic Valve Manifold, shown in fi gure 52.

This valve manifold includes a 3-station manifold with two single-sole-noid, 2-position DCV’s, and one double-solenoid, 2-position detent DCV, all with manual overrides.

PROGRAMMABLEPOSITION

PNEUMATICMANIPULATOR

ELECTRO-PNEUMATIC

VALVEMANIFOLD

4 CHANNEL PARTS

STORAGE MODULE


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9. Perform the following substeps to familiarize yourself with the components that are common to all stations.

Each mobile workstation has an operator panel, controller, digital interface module, and pneumatic distribution module, as shown in fi gure 53, and electrical distribution module.

Figure 53. Common Station Components

DIGITALINTERFACE

MODULE

CONTROLLER

PNEUMATICDISTRIBUTION

MODULE

OPERATORPANEL


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A. Locate the Operator Panel, shown in fi gure 54. Each operator panel includes a Start pushbutton and Output Power

pushbutton. Each of these pushbuttons has a built-in lamp. These lamps are separately wired to the PLC. The PLC is typically programmed to turn on a lamp after its pushbutton is pressed. Also, you will fi nd a Stop pushbutton, Auto/Manual/ Reset selector switch, and a Main Power (safety) switch. The main power switch has a location for an electrical lockout. Each panel also includes an Emergency Stop pushbutton that lights up when it is pushed in.


AUTO/MANUAL/RESETSELECTOR SWITCH

OUTPUT POWERPUSHBUTTON

MAINPOWERSWITCH

EMERGENCYSTOP

PUSHBUTTON

OUTPUTPOWER

LAMP (WHITE)

STOPPUSHBUTTON

STARTPUSHBUTTON

STARTLAMP

(GREEN)


55

B. Locate the Controller, shown in fi gure 55.

The controller is a Siemens S7300 series Programmable Controller, either model 313, 314, or 315. It also includes a portable PLC mounting console, 24VDC power supply, and a master control relay.

Figure 55. Controller

24 VDCPOWERSUPPLY

PORTABLEMOUNTINGCONSOLE

CONTROLLER

MASTERCONTROL

RELAY


56

C. Locate the Pneumatic Distribution Module, shown in fi gure 56.

The pneumatic distribution module includes the air regulator, pressure gauge, fi lter, and pneumatic lockout valve.

Figure 56. Pneumatic Distribution Module

AIRREGULATOR

PRESSUREGAUGE

PNEUMATICLOCKOUT

VALVE

FILTER


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D. Locate the Electrical Distribution Module, shown in fi gure 57.

The electrical distribution module is located in the back of the station and includes the power distribution cable, power supply cable, electrical power outlets.

Figure 57. Electrical Distribution Module (Shown from Rear of Station, looking up)

POWERDISTRIBUTION

CABLE

ELECTRICALPOWER

OUTLETS

POWERSUPPLYCABLE


58

E. Locate the Digital Interface Module, shown in fi gure 58.

The digital interface module includes terminal blocks with 72 input/output control terminals near the operator panel used for the wiring interface between the PLC and the automated components. It also includes terminal blocks with 72 separate terminal sets for power to I/O.

Figure 58. Digital Interface Module

DIGITALINTERFACE

MODULE


59


1. A machine sequence is a programmed series of _________ or steps.

2. Each step of a control system sequence starts with an input signal, the ________ then decides which output to turn on or off, then the machine step takes place.

3. To create a sequence of steps, the __________ devices are physically arranged on the machine so completion of one step triggers the start of the next step.

4. Three types of pushbuttons are the extended button, ____________ head, and the fl ush button.

5. The four types of manual discrete output devices are indicator lamps, audible alarms, message displays, and ______________.

6. A limit switch is an input switch that senses the position of a machine component by ___________ means.

7. An _____________ proximity sensor creates a magnetic fi eld that is used to sense when a metal part comes into range.

8. A fi ber optic sensor is a __________ sensor that uses fi ber optic fi laments to send and receive the light.

9. A giant magnetoresistive sensor is a magnetic sensor that responds mainly to the magnetic fi eld orientation and ___________ rather than the magnetic fi eld strength.

10. Two types of automatic discrete output devices are directional control valves and _____________.


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SEGMENT 3MECHATRONICS SAFETY

OBJECTIVE 10 DESCRIBE EIGHT MECHATRONICS OPERATORSAFE DRESS RULES

Safety is the highest priority in all modern industrial plants. Companies strive to increase the productivity while at the same time ensuring that no one is injured. Jobs that involve mechatronics equipment can be very dangerous because there are fast moving parts through which high forces are often transmitted.

The fi rst line of defense against accidents with automation equipment is proper dress, as shown in fi gure 59.

Figure 59. Safety Attire when Working with Running Machinery

SAFETYGLASSES

ROLLEDSLEEVES

HEAVY-DUTYBOOTS

HEARINGPROTECTION


61

The following rules will help ensure safety when working around industrial equipment. Most companies have specifi c safety rules that may vary from those given here. For example, some jobs may require that a person wear a long sleeve protective garment.

• Wear safety glasses

Figure 60. Safety Glasses

• Wear hearing protection• Avoid wearing loose fi tting clothes• Remove ties, watches, rings, and other jewelry• Tie up long hair, put it under a cap or tuck it into a shirt• Wear heavy-duty leather shoes, steel-toed shoes are recommended. Canvas shoes are not acceptable.• Roll up long sleeves or wear short sleeves• Do not wear gloves around machinery when it is running. Gloves can get caught in the moving components and pull a hand into the machine.

Figure 61. Do Not Wear Gloves


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OBJECTIVE 11 DESCRIBE EIGHT MECHATRONICS OPERATOR SAFETY RULES

Mechatronics equipment can be very dangerous because it can change its posi-tion very quickly. Apply the following safety rules any time work is performed around mechatronics equipment.

• Do not enter a machine’s area of operation until the machine is completely stopped.• Perform a lockout/tagout on all power sources before starting a maintenance operation.

Figure 62. Lockout/Tagout

• After locking out the system, remove any pressure (air or hydraulic) left in the system. Operating the DCV’s manual overrides a few times should remove any remaining pressure.• Properly secure a hose or device that contains compressed air. Fittings can blow out if they are not secure. Mechanically test or pull connections before pressurizing. Gradually increase the air pressure where possible while observing for loose lines or bad connection.• Remove all obstructions from the work area.• Check for signs of damage to equipment.• Remove robot teach pendants from the work area.


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• Locate all emergency stop pushbuttons.

Figure 63. Emergency Stop Pushbutton


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OBJECTIVE 12 DESCRIBE THE OPERATION OF AN ELECTRICAL LOCKOUT/TAGOUT SYSTEM

An electrical lockout/tagout system is a method of preventing all electrical power from being restored to a machine or workcell while work is being performed on it. An electrical lockout/tagout system has three main components: lock, lockout hasp, and a tag. The lockout hasp uses a scissors action to hook through the slots in a safety switch, as shown in fi gure 64. This prevents the power switch from being placed in the ON position. Once the hasp is fully closed, the holes in the bottom section are aligned. The lock is installed through one of these holes, also shown in fi gure 64, to prevent the removal of the hasp. Before the lock is closed, a tag is added to identify the lock’s owner and the date the lockout was performed.

Figure 64. Electrical Lockout/Tagout

Every person working on a machine must install his or her own lock. The lockout device has holes for fi ve locks. The sixth hole is used to install another lockout hasp to ensure that there are always available holes for additional locks.

POWERSWITCH

MULTIPLELOCKOUT HASP

LOCK

TAG


65

SKILL 2 PERFORM A LOCKOUT/TAGOUT ON AN ELECTRICAL SYSTEM

Procedure Overview

In this procedure, you will perform a lockout/tagout procedure on the electrical disconnect safety switch of the 870 Mechatronics station. This procedure is the same for each mechatronics station, so this skill only needs to be performed on one station.

1. Check out a padlock, a lockout hasp, and a tagout tag, as shown in fi gure 65. This will be used to perform a lockout/tagout on the electrical system.

Figure 65. Lockout/Tagout Devices


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2. Perform the following substeps to perform a lockout/tagout on the 870’s electrical system.

A. Go to one of the 870 stations and locate the safety switch on the front the Operator Panel, as shown in fi gure 66.

Figure 66. Safety Switch for an 870 Station

SAFETYSWITCH


67

B. Make sure the lever of the safety switch is in the Off position (down), as shown in fi gure 67. If it is not, place it in the off position by pressing down on the switch lever.

Figure 67. Safety Switch in the Off Position

(DOWN)OFF

POSITION


68

C. Locate one lockout hasp and open it as shown in fi gure 68.

Figure 68. Lockout Hasp Opened


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D. Hook the lockout hasp through the slots in the switch bracket. Then, close the hasp, as shown in fi gure 69.

Figure 69. Lockout Hasp Installed and Closed

E. Fill in the appropriate information on the tag (your name, the class, and the date). If you have a lab partner, he/she should sign the tag also.

Keep in mind that some instructors may require a tag for each individual person.

F. Open your lock and hook it through the hole in the top of the tagout tag, as shown in fi gure 70.

Figure 70. Lock Hooked Through the Tagout Tag


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G. Install the lock and tagout tag on the lockout hasp, as shown in fi gure 71.

If you are the only one who will be locking the device out, or if you are the fi rst to install your lock, use one of the top holes of the lockout hasp. Others can use the remaining holes for their locks if they will be working on the device.

The electrical safety switch is now locked out and tagged out. No one can operate the safety switch until the lockout and tag have been removed from the safety switch.

Figure 71. Lockout/Tagout Installed on the Electrical Safety Switch

3. Have your instructor check your work to make sure the lockout/tagout is done properly.

4. Leave the lockout/tagout devices in place for the next skill unless your instructor advises you otherwise.


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OBJECTIVE 13 DESCRIBE THE OPERATION OF A PNEUMATIC LOCKOUT/TAGOUT SYSTEM

To ensure safety, all power sources must be locked out for service or mainte-nance. Pneumatic actuators can operate even though electrical power is locked out because the compressed air is still being provided to the system. Because of this, pneumatic systems are also often equipped with a lockout/tagout system.

A pneumatic lockout/tagout has four main components: a lockout valve, lockout hasp, lock, and a tag. When the valve is in its closed position, the lockout hasp is placed through a slot in its lever. This prevents the valve from being shifted to its open position. The lock is installed through one of the holes in the lockout hasp, as shown in fi gure 72, to prevent the removal of the hasp. Before the lock is closed, a tag is added to identify the lock’s owner and the date the lockout was performed.

Figure 72. Pneumatic Lockout/Tagout

INLET

LOCK

LOCKOUTVALVE

OUTLET

HASP

TAG


72

The lockout valve is a two-position valve that allows fl ow through the valve in one position and blocks the supply line while venting the downstream air pres-sure in the other, as shown in fi gure 73. While the valve is being shifted from Closed to Open, air is supplied to the system and is also being vented, as shown in center of fi gure 73. This allows the slow build-up of pressure in the system to avoid damaging any downstream components. When fully open, the valve allows air to fl ow to the system, as shown on the right side of fi gure 73.

Figure 73. Lockout Valve Operation

CLOSED POSITION PARTIALLY OPEN OPEN POSITION

SUPPLYBLOCKED

VENTINGDOWNSTREAM

PRESSURE

PROVIDESSLOW INCREASE

IN PRESSURE

PUSH

FULL FLOWTO SYSTEM

LOCKOUTVALVE

LOCKOUTVALVELEVER


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SKILL 3 PERFORM A LOCKOUT/TAGOUT ON A PNEUMATIC SYSTEM

Procedure Overview

In this procedure, you will perform a lockout/tagout procedure on the pneumatic shut-off valve of the 870 Mechatronics station. This procedure is the same for each mechatronics station, so this skill only needs to be performed on one station.

1. Check out a padlock, a lockout hasp, and a tagout tag, as shown in fi gure 74. This will be used to perform a lockout/tagout on the pneumatic system.



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2. Perform the following substeps to perform a lockout/tagout on the 870’s pneumatic system.

A. Go to one of the 870 stations and locate the pneumatic lockout valve, shown in fi gure 75.

Figure 75. Lockout Valve for an 870 Station

B. Make sure the lever on the lockout valve is in the Closed position (pushed forward), as shown in fi gure 76. If it is not, push the lever forward until the hole for the lockout lock is visible.

Figure 76. Lockout Valve in the Closed Position

PNEUMATICLOCKOUT

VALVE

CLOSEDPOSITION

LOCKOUTHOLE


75

C. Install the lockout hasp through the slot in the center of the lever, as shown in fi gure 77.

Figure 77. Lockout/Tagout Installed on the Pneumatic Locked Valve

D. Fill out the tag with the appropriate information.

E. Install the lock and tag to the lockout device.

The lockout valve is now locked out and tagged out. No one can restore pneumatic pressure until the lockout and tag have been removed from the valve.

3. Have your instructor check your work to make sure the lockout/tagout is done properly.

4. Leave the lockout/tagout devices in place for the next skill unless your instructor advises you otherwise.


76


1. When working around automated machinery, it is important to wear vision and hearing protection, tie up long hair, and roll up ___________.

2. When performing maintenance on a machine, every person working on the machine must install his or her own ___________.

3. One of the most important safety rules to follow before performing maintenance on a machine is to perform a lockout/tagout on _____________.

4. An electrical logout/tagout prevents electrical power from being __________ while work is being performed.

5. Pneumatic actuators can still operate after ___________ power has been locked out.

6. A pneumatic lockout valve is a two-position valve that allows fl ow through the valve in one position and blocks the supply line while ___________ the downstream pressure in the other.


77

SEGMENT 4MACHINE OPERATOR FUNCTIONS

OBJECTIVE 14 DESCRIBE THE ROLE OF A MODERN AUTOMATEDMACHINE OPERATOR

Traditionally, the role of a machine operator has been to start and stop the machine, load parts, make adjustments to its settings, and monitor the machine. In the age of lean manufacturing, the operator’s role in most automated facilities has become much more sophisticated, including functions such as using a computer-based operator terminal, performing quality assurance tasks, and performing basic machine maintenance. By performing these additional functions, operators have a much more valuable role.

Figure 78. Operator Terminal


78

OBJECTIVE 15 DESCRIBE THE FUNCTION OF A BASIC OPERATOR PANEL

The traditional operator panel uses discrete pushbuttons, selector switches, and indicators to help the operator monitor and control the machine’s operation. The typical functions these operator panels may contain include:


Machine Start

A start pushbutton is often used to start the machine cycle. Typically, this is a green, fl ush, momentary contact pushbutton. Often the button will have a built-in indicator light that tells the operator at a glance that the machine cycle has been started. This light is turned on by a PLC output. It does not turn on by simply pressing the pushbutton.

Machine Cycle Stop

A cycle stop pushbutton is used to stop the machine at the end of its current sequence. This is considered a normal stop because all actuators return to their start positions and pressing the start button will begin the sequence again. The cycle stop is used to stop the machine in the event of a break, end of shift, or if the operator is out of parts. A red, extended, or fl ush, momentary contact pushbutton is commonly used for the cycle stop function. It is not intended for use as an emer-gency stop.

The National Electrical Manufacturers Association standard ICS 5 requires that any pushbutton that performs a stop function must be red.

OPERATOR PANEL

MANUALAUTO JOG

READY RUNNING FAULT STOPPED

STARTCYCLESTOP HALT

EMERGENCYSTOP


79

Emergency Stop

Every operator panel should include an emergency stop pushbutton that will remove power as quickly as possible. This button must be a red, maintained-contact type and is typically a large, mushroom-shaped button that can be hit quickly. Often, the button is illuminated so the operator can tell at a glance that the button is engaged.

Manual/Automatic

Almost all automatic machines have the ability to operate in either a manual or automatic mode. On a traditional operator panel, a selector switch controls this function. Some mode selector switches are two-position with automatic and manual modes, while some are 3-position types with either an off function or a reset function in addition to the automatic or manual modes.

Jog

The process of operating one of the machine’s actuators in the manual mode is called jogging. Jogging is most often performed by operating a pushbutton or selector switch on the operator panel. This causes the actuator to move in one direction while a pushbutton or selector switch on the operator station is actuated. The jog function also can be performed using manual overrides on devices such as fl uid power valves or motor starters.

In many machines the manual mode is programmed into the PLC that controls the machine. It is activated by placing a selector switch on the operator station in the manual position while the PLC is on and in the RUN mode. The PLC ladder logic assigns pushbutton inputs to control outputs that jog the machine’s actuators. The manual portion of the PLC program is written so that any sensors that may be triggered while the actuators are jogged do not affect the PLC’s operation.

Halt

Many operator panels include a Halt pushbutton. The halt function is used to stop the sequence of an automated machine after the current step. All power remains on and the start pushbutton will resume the sequence provided all inputs remain unchanged. This function is often included in equipment where the oper-ator may need to pause the cycle for some reason. Activating the halt function is usually done through the use of a red, extended, momentary-contact pushbutton.


80

Indicator Lights

Indicator lamps are used on an operator panel to tell the operator at a glance the status of the machine. Depending upon the purpose of the indicator lamp, it may be programmed to be on the entire time it is active or blink to catch the eye of the operator.

There are a many lens colors available for indicator lamps. Each color repre-sents a different status, as shown in the following table.

LENS COLOR TYPICAL FUNCTION EXAMPLE

Red Danger, Abnormal Condition, Fault Condition

Voltage applied; cycle in automatic; faults in air, water, lubrication or fi ltering systems; ground detector circuits.

Amber(Yellow)

Attention Motors running; machine in cycle; unit or head in forward position.

Green Safe Condition (security) End of cycle; ready for cycle; cycle running; unit or head returned; motors stopped; motion stopped; contactors open.

White or Clear Normal Condition Normal pressure of air, water, lubri-cation.

Figure 80. Indicator Lens Color Functions


81

OBJECTIVE 16 DESCRIBE THE OPERATION OF THREE CATEGORIES OF STOP FUNCTIONS

A global standard exists that defi nes the methods used to safely stop machines for various applications. This standard has three categories, which include:

• Stop Category 0 - This stop category immediately removes power to the machine actuators. It is an uncontrolled stop because no power is available to brake the actuators. The motors will spin freely and coast to a stop over a period of time. A category 0 stop is higher in priority than category 1 or 2 stop functions.Stop Category 0, which is often used as an emergency stop must be initi-ated by one human action and must override all other machine functions and operating modes. Typically, the output power is removed using a master control relay. • Stop Category 1 - A category 1 stop is a controlled stop, which means that power is available to the machine actuators to brake to a full stop. Power is then removed after the stop is achieved. • Stop Category 2 - A category 2 stop is controlled stop with power left avail-able to the machine actuators. This is considered a normal production cycle stop or halt function. This stop category stops at the end of the current move-ment or current cycle depending on its programming.

Figure 81. Stop Functions

COMPONENTSTOP

CYCLE STOP(CATEGORY 2)

EMERGENCY STOP(CATEGORY 0)


82

OBJECTIVE 17 DESCRIBE HOW TO OPERATE AN AUTOMATED MACHINE

Automated machines vary by design and operation, but there are a number of operation steps that are typical of most machines. The following is a general guide-line to starting up, operating, and shutting down automated machines. Always review the operator instructions for a specifi c machine before operating it.

Step 1: Perform Safety Checks

Before applying power to any machine, certain safety issues must be addressed. The work area must be clear of personnel and obstructions, which includes looking the equipment over to make sure there are no tools or maintenance components such as chocks or supports left in a work area. Check for fl uid leaks that can indi-cate a problem with the equipment and/or create a slipping hazard. If any equip-ment panels are left open, check with maintenance to verify the equipment has been tested and is ready to run. Verify that all safety guards are in place.

Step 2: Prepare Machine for Startup

This step may involve stocking parts in feeders, using the mode selector switch to put the equipment in manual mode so it does not start up when power is applied, or checking/replacing tooling.

Step 3: Remove Lockout/Tagout Devices

Remove any lockout/tagout devices on electrical, pneumatic, hydraulic, or mechanical power sources.


HASP


83

Step 4: Power Up the Machine

This step involves turning on all power to the equipment and may include: • Turn on the main power switch or electrical disconnect - The main power switch is normally located on the operator panel while a disconnect switch may be mounted in a nearby location.• Turn on air and/or water - The air supply is restored using either an air regu-lator or shutoff valve and the water supply typically uses a shutoff valve.• Turn on hydraulic power supply - Hydraulic power is supplied by a hydraulic pump driven by a prime mover such as an electric motor. Check the hydraulic fl uid level in the reservoir to verify that it meets operating requirements and then start the pump.• Check/set pressures on air/water/hydraulic - Check the fl uid pressure and set to operating levels. Air uses a regulator for pressure adjustments. Water is typically regulated with a valve, such as a globe or gate valve or it may have a regulator. Hydraulic pressure is controlled through a relief valve or pump compensator.

Step 5: Turn on PLC Output Power

Verify that the PLC’s modules are powered up. They often have a separate power switch or pushbutton that controls the output power.

Step 6: Home or Reset All Machine Actuators and Robots

This step sets each actuator back to the home position and makes sure the machine is ready for start up. This is often done with a reset selector switch or with individual actuator reset pushbuttons on the operator panel. Robots are put into run mode at this time.


84

Step 7: Place System in Auto Mode

Put the system in Auto mode for operation. Typically this is done with a selector switch on the operator panel.

Figure 83. Power Up the Machine

Step 8: Start Operation

Operation of automated equipment usually starts when the operator presses the start pushbutton. Although the equipment is automated, an operator is typically nearby to reload part feeders, clear part jams, and observe operation.

1

3

POWER SYSTEM PRESSURE READY CYCLE ACTIVE

BRAKE CONTROL

FORWARD(ACTIVATE)

REVERSE(DEACTIVATE)

LOAD CONTROLLOAD SELECTION

CYCLE START CYCLE STOP PROGRAM

MANUALIDLE

AUTO

CYCLE

CYCLESELECTOR

SWITCH


85

Step 9: Stopping the Machine

Typically, there are three planned-for types of stop functions that can be programmed into a machine: halt, cycle stop, and emergency stop. Most machines have two or three of these functions.

The halt stop function stops the equipment at the end of the current move-ment without removing power. This pushbutton can be pressed any time during the cycle. This function is used to temporarily pause operation for some non-emer-gency reason. Halt functions are typically programmed so that pushing the start pushbutton again resumes the program where it left off.

The cycle stop function, once initiated, stops the equipment once the current cycle fi nishes. This pushbutton can be pressed at any time during the cycle. This function is used to stop the cycle for a break or at the end of shift because it stops the equipment in its home position, ready for the next cycle. Power is still on and typically the cycle can be started again once the start pushbutton is pushed.

The emergency stop function removes all electrical power immediately to the machine’s actuators. This typically reinitiates all programs in memory as well. This function is used when damage to the equipment or personal injury is likely to occur. When the cause for pressing the emergency pushbutton has been cleared, the emergency pushbutton is pulled out, power is restored to outputs, all machines are reset, homed, and the cycle restarted by pressing the start pushbutton.

A power loss during the middle of a cycle acts much like an emergency stop. After power is restored, all equipment must be reset, homed, programs reiniti-ated, and the cycle restarted by pressing the start pushbutton. Parts may have to be removed from the equipment so that a new cycle can be started. There are times that a power outage may cause some unforeseen problems with the equipment, so it is always a good idea once power is restored to test the equipment and program without parts or to test it manually to make sure that it runs as designed.

Step 10: Shutdown

Once the system is stopped at the end of the cycle, the shutdown procedure can be performed. This includes:

• Shutting down any computers • Turning off all power supplies to the equipment (air, water, electric, hydraulic)• Performing lockout/tagout procedures on all power supplies.


86

SKILL 4 POWER UP AN AUTOMATED MACHINE

Procedure Overvide

In this procedure, you will perform a power up and power down sequence on the 870 Mechatronics Station. This procedure is the same for each mechatronics station, so this skill only needs to be performed on one station. The power up sequence includes steps 1-5 of the startup sequence presented in the previous objective.

1. Locate a Mechatronics station. 2. Verify that this station has been separated from any other stations. If it has

not, then proceed with Step 3 to separate it from the other station. If it has, then proceed to Step 4.

3. Perform the following substeps to separate the station from the other stations.

A. Verify that the station power cord has been removed from the wall outlet.

B. Remove the adjoining station’s power cord at the back of the station.

Figure 84. Adjoining Power Cord Removed (Shown from Rear of StationA)

ADJOININGSTATION'S

POWER CORD

STATIONPOWERCORD


87

C. Remove the adjoining station’s pneumatic hose.

Figure 85. Pneumatic Hose (Shown from Rear of Station)

D. Disconnect 9-pin to 9-pin cable from the station.

Figure 86. 9-Pin Cable

ADJOININGSTATION'S

PNEUMATICHOSE

9-PIN CABLE


88

E. Loosen the connecting fasteners that hold the work surfaces together by turning the thumbscrews CCW.

Figure 87. Connecting Fasteners

F. Remove the thumbscrew and set aside.

G. Push the station away from the other stations to give yourself room to work.

4. Perform the following safety check before you begin working on the station. Make sure that you can answer yes to each item before proceeding.

YES/NO SAFETY CHECKOUT

Remove all obstructions from the work area

Check for signs of damage to the equipment

Wear tight fi tting clothing, roll up long sleeves, remove ties, scarves, jewelry, etc.

Tie up long hair

Remove any robot teach pendants from the work area

Locate the emergency stop button

Ensure that safety glasses are worn by people in area

Ensure that all people are outside any work envelopes

Figure 88. Mechatronics Safety Check

TURNCCW


89

5. Connect an air supply to the air manifold’s quick connect in the back of the station as shown in fi gure 89.

Figure 89. Station Air Hose Attached to Compressed Air Supply

STATIONAIR HOSE

COMPRESSEDAIR SUPPLY


90

6. Plug the station’s electrical cord into a power outlet. If the power cord is not attached to the station, locate it in the back of the station and plug the female end into the station’s power plug under the work surface at the back of the station, as shown in fi gure 90. Then plug the other end into the wall outlet.

There will be no visual indication that power has been applied to the station. Plugging the power cord into the outlet brings power to the back of the station.

Figure 90. Station Power Cord Attached to Wall Outlet

7. Place the mode selector switch in the Manual mode setting by turning the selector switch.

Figure 91. Mode Selector Switch Set to Manual Mode

STATION’SPOWER PLUG

STATIONPOWERCORD


91

8. Remove the lockout/tagout device from the electrical power source. 9. Remove the lockout/tagout device from the pneumatic power source. 10. Turn on the air to the station by shifting the lever on the lockout valve. 11. Turn on the Main Power switch. Allow the PLC a couple of minutes to go through its boot sequence. You

should see the following PLC indicator lights turn on:• Run or Stop - depends on the placement of the PLC switch• PLC input power (DC5V)• Various PLC inputs, depending on the station

There will be no control panel indicator lights active at this time.

Figure 92. Station Indicators

12. Push the Output Power button On. This will activate power to the outputs on the station’s PLC. You should hear

the contactor next to the PLC modules pull in, indicating that output power is now on.

PLCINDICATORS

INPUTINDICATORS


92

13. Verify that the following indicator lights are on:• Output Power button • Various PLC outputs• The Start pushbutton indicator will be off if the station is ready for opera-tion. If the actuators are not in the home or reset position, the indicator will be blinking until the actuators are reset.

Figure 93. Output Indicators

14. Perform the following substeps to review the pneumatic connections on the station shown in fi gure 94.

Figure 94. Pneumatic Connections

OUTPUTINDICATORS

MALECONNECTION

SHUTOFF

SHUT OFF VALVEWITH LOCKOUT

BRANCHLINE

AIRFILTER

PRESSUREGAUGE

TO COMPONENTS

RELIEVINGREGULATOR

FEMALECONNECTION


93

A. Locate the male air connection shown in the fi gure.

This connection is used to connect to the main air source if the station is running alone or if it is the fi rst station. If multiple stations are connected together, the incoming air supply would be connected here. This connec-tion is always used.

B. Locate the female air connection shown in the fi gure.

This connection is used to connect air from one station to the next in a daisy chain to prevent the need to run separate hoses from the air supply to each station. This connection is used only if multiple stations are connected together.

C. Locate the shut off valve shown in the fi gure.

This valve is a lever-operated valve with a lockout. This is where the pneu-matic power for the station is locked out. Locking out this station will not remove pneumatic power from any of the other connected stations. Each station’s pneumatic power must be locked out individually.

D. Locate the air regulator shown in the fi gure.

The air regulator provides the means for adjusting the working air pres-sure. This type of regulator is a relieving regulator, which means that air can fl ow back through the regulator to relieve pressure in the system. It includes an air fi lter to clean the air and a gauge to measure the working air pressure.

Once the air leaves the regulator, it moves on to the components on top of the station.

15. Perform the following substeps to review the electrical connections on the station shown in fi gure 95.

Figure 95. Electrical Connections

POWERCORD PLUG

INCOMING POWERSUPPLY

N

L1

GND

MAINPOWER

(ON/OFF)SWITCH

24 VDCPOWER SUPPLY

FEMALEDAISYCHAIN

RECEPTACLE

MALE RECEPTACLEMAIN POWER

N L

+V +V -V -V


94

A. Locate the Power cord shown in fi gure 95.

This brings power from the wall outlet to the station.

B. Locate the Male receptacle shown in fi gure 95.

This is where the main power cord is connected to the station.

C. Locate the Female receptacle shown in fi gure 95.

This receptacle is used to bring power from one station to the next. This receptacle is used only if multiple stations are connected together.

D. Locate the On/Off switch shown in fi gure 95.

This switch is a safety switch that includes a location for an electrical lockout. It also includes a 7-amp circuit breaker to protect the equipment in the event too much power comes into the system.

E. Locate the 24VDC Power Supply shown in fi gure 95.

This power supply changes the incoming power to 24VDC for use by the system. It also provides power to the terminal blocks where the compo-nents are wired.

If the station were connected to another station, as shown in fi gure 96, the connections would appear as shown.

Figure 96. Stations Connected Together

POWERCORD PLUG

INCOMING POWERSUPPLY

N

L1

GND

MAINPOWER

(ON/OFF)SWITCH

FEMALEDAISYCHAIN

RECEPTACLE

MALE RECEPTACLEMAIN POWER

TO MALERECEPTACLE

ON NEXTSTATION

24 VDCPOWER SUPPLY

N L

+V +V -V -V


95

16. Review a wiring diagram of the station shown in fi gures 97 - 99. Figure 97 shows which components are powered when the main power switch

is turned on. The 24V power supply and the PLC processor are powered up and the PLC status indicators DC5V and Run should be turned on as well as some of the PLC input module’s indicators, such as the Stop pushbutton and the Emergency Stop pushbutton. The specifi c indicators will depend on the station.

ESR stands for emergency stop relay. When multiple stations are running together and the E-stop button on a middle station is pressed, Emergency Stop Relay A will cause all previous stations to perform an emergency stop. Emergency Stop Relay B causes that station as well as any stations down the line to perform an emergency stop.

Figure 97. Wiring Diagram for Main Power ON

POWER CORD PLUGINCOMING

POWER SUPPLY

N

L1

GND

OUTPUTPOWER PB

ESRA ESRBCC1

OUTPUTPOWER

INPUTSPLC CPU

DC5V

RUN

PROCESSORON

MAINPOWERSWITCH

POWERSUPPLY

ON

INPUTMODULE

ON

EMERGENCY STOP PB

STOP PB

PLUG

OUTPUTS

+V COM

+V COM

+V COM

OUTPUTDEVICE

CC1a

CC1b

24 VDCPOWER SUPPLY

N L

+V +V -V -V


96

Figure 98 shows which components are powered when the Output Power pushbutton is pressed. In addition to the indicators mentioned above, once the Output Power button is pressed the contactor for the output power is energized, which powers up PLC Output module, which turns on the Output Power indicator lamp. Various inputs and/or outputs, depending on the station, are also active at this time.

Figure 98. Wiring Diagram for Output Power On

OUTPUTPOWER PB

ESRA ESRBCC1

OUTPUTPOWER

INPUTSPLC CPU

DC5V

RUN

CONTACTORON

OUTPUTPOWER

ON

INDICATORLIGHT ON

OUTPUTSENABLED

OUTPUTS

+V COM

+V COM

+V COM

OUTPUTDEVICE

CC1a

CC1b

ENERGIZED

TO -24VPOWER SUPPLY

TO +24VPOWER SUPPLY


97

Figure 99 shows which components are powered when the Start pushbutton is pressed.

In addition to the components previously mentioned, the Start pushbutton is active and various inputs and outputs are active as the station moves through its sequence.’

Figure 99. Wiring Diagram for Start Pushbutton On

17. Perform the following substeps to power down the station.

A. Turn the Main Power switch Off.

B. Perform a lockout/tagout on the system’s electrical power source.

C. Perform a lockout/tagout on the system’s pneumatic power source.

OUTPUTPOWER PB

ESRA ESRBCC1

OUTPUTPOWER

INPUTSPLC CPU

DC5V

RUN

START PB

OUTPUTS

+V COM

+V COM

+V COM

OUTPUTDEVICE

CC1a

CC1b

TO -24VPOWER SUPPLY

TO +24VPOWER SUPPLY

START PBINDICATOR

LAMP


98


1. Today’s machine operator must use a computer-based operator terminal, perform quality tasks, and perform basic machine _____________.

2. A cycle stop, when pressed, stops the machine at the end of _____________.

3. An emergency stop removes power _____________.

4. The process of operating one of the machine’s actuators in the manual mode is called ____________.

5. A halt function stops the machine at the end of ______________.

6. A stop category 0 _____________ removes power to the machine actuators.

7. A category _______ stop is considered a normal production cycle stop or halt.

8. The fi rst step in operating an automated machine is to perform _____________.

9. Before placing the automated equipment in Auto cycle, you should fi rst _____________ all machine actuators and robots.

10. The very last step in shutting down a machine is to perform a ____________ on all power supplies.

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