TM-297

080673

OPERATION AND MAINTENANCE MANUAL

with

ILLUSTRATED PARTS LIST

for

GENERATOR SET

Hobart Model MG 1028

28.5 V DC, 28.5 KW, 1000 A.

Specification 5651

and Variations

Manufactured by

MOTOR GENERATOR DIVISION

HOBART BROTHERS COMPANY

TROY, OHIO 45373

U.S.A.

SAFETY INSTRUCTIONS AND WARNINGS FOR ELECTRICAL POWER EQUIPMENT

A WARNING ELECTRIC SHOCK can kill. Do not touch live electrical parts.

FUMES &ND GASES can be fire and health hazards. Ventilate all fumes and exhaust gases to the outside.

ELECTRIC ARC FLASH can injure eyes, burn skin, cause equipment damage, and ignite combustible material. Do not

use power cables to break load and be sure tools don’t cause short circuits.

IMPROPER PHASE CONNECTION, PARALLELING, OR USE can damage this and attached equipment.

MOVING PARTS can cause serious injury. Keep clear of moving parts.

IMPORTANT - Protect yourself and others. Read and understand all the instructions in this Operating/Instruction

Manual before installing, operating, or servicing this equipment. Keep this manual available for future

use by all operators.

A.

6.

GENERAL

Equipment that supplies electrical power can cause serious injury or death, or damage to other equipment or

property, if the operator does not strictly observe all safety rules and take precautionary actions. Safe practices

have developed from past experience in the use of power source equipment. Certain of the practices below apply to

engine driven equipment.

SHOCK PREVENTION

Bare conductors, or terminals in the output circuit, or ungrounded, electrically-live equipment can fatally shock a

person. Have a competent electrician verify that the equipment is adequately grounded and learn what terminals

and parts are electrically HOT. Use proper safety clothing, procedures, and test equipment.

The electrical resistance of the body is decreased when wet, thus more easily permitting dangerous currents to flow

through it. When inspecting or servicing equipment, do not work in damp areas without being extremely careful.

Stand on dry rubber mat or dry wood, use insulating gloves that are effective when dampness or sweat cannot be

avoided. Keep your clothing dry and never work alone.

1. Installation and Grounding of Electrically Powered Equipment - Electrical equipment must be installed

and maintained in accordance with the National Electrical Code, ANSI/NFPA 70, and other applicable codes.

A power disconnect switch or circuit breaker must be located at the equipment. Check the nameplate for voltage,

frequency, and phase requirements. If only 3-phase power is available, connect any single-phase rated equipment to

only two wires of the S-phase line. DO NOT CONNECT the equipment grounding conductor (lead) to the third live

wire of the 3-phase line, as this makes the equipment frame electrically HOT, which can cause a fatal shock -- --- ---*

Be sure to connect the grounding lead, if supplied in a power line cable, to the grounded switch box or building

ground. If not provided, use a separate grounding lead. Be certain that the current (amperage) capacity of the

grounding lead will be adequate for the worst fault current situation. Refer to the National Electrical Code ANSI/

NFPA 70 for details. Do not remove plug ground prongs. Use correct mating receptacles.

2. Output Cables and Terminals - Inspect cables often for damage to the insulation and the connectors. Replace

or repair cracked or worn cables immediately. Do not overload cables. Do not touch output terminal while equip-

ment is energized.

Instruction 910082

Nov 16182 Revised

Page 1

C.

D.

E.

F.

G.

1 I 3. Service and Maintenance - This equipment must be maintained in good electrical and mechanical condition

to avoid hazards stemming from disrepair. Report any equipment defect or safety hazard to your supervisor and

discontinue use of the equipment until its safety has been assured. Repairs should be made by qualified personnel

only. Shut OFF all power at the disconnecting switch or line breaker before inspecting or servicing the equipment.

Lock switch OPEN (or remove line fuses) so that power cannot be turned ON accidentally. Disconnect power to

equipment if it is out of service. If troubleshooting must be done with the unit energized, have present another per-

son trained in turning off the equipment and providing or calling for first aid.

’ FIRE AND EXPLOSION PREVENTION

Fire and explosion are caused by electrical short circuits, combustible material near engine exhaust piping, misuse

of batteries and fuel, or unsafe operating or fueling conditions.

1. Electrical Short Circuits and Overloads - Overloaded or shorted equipment can become hot enough to cause

fires either by self destruction or causing nearby combustibles to ignite. Provide primary input protection to re-

move short circuited or heavily overloaded equipment from the line.

2. Battery - Batteries may explode and/or give off flammable hydrogen gas. The acid and arcing from a ruptured

battery can cause fires and additional failures. When servicing, do not smoke, causing sparking, or use open flame

near the battery.

3. Enoine Fuel - Use only approved fuel container or fueling system. Fires and explosions can occur if the fuel

tank is not grounded prior to and during fuel transfer. Shut unit DOWN before removing fuel tank cap. Do not

completely fill tank. Heat from the equipment may cause fuel expansion overflow. Remove all spilled fuel im-

mediately including any that penetrates the unit. After cleanup, open equipment doors and blow fumes away with

compressed air.

TOXIC FUME PREVENTION

Carbon Monoxide - Engine exhaust fumes can kill and cause health problems. Pipe or vent the exhaust fumes to a

suitable exhaust duct or outdoors. Never locate engine exhausts near intake ducts or air conditioners.

BODILY INJURY PREVENTION

Serious injury can result from contact with fans, belts, and pulleys inside the equipment. Shut DOWN equipment

for inspection and routine maintenance. When equipment is in operation use extreme care in doing necessary

troubleshooting and adjustment.

MEDICAL AND Fl RST AID TREATMFN

First aid facilities and a qualified first aid person should be available for each shift for immediate treatment of ail

injury victims. Electric shock victims should be checked by a physician and taken to a hospital immediately if any

abnormal signs are observed.

EMERGENCY FIRST AID

Call physician immediately. Seek additional assistance and use First Aid techniques recommended

by American Red Cross until medical help arrives.

IF BREATHING IS DIFFICULT, give oxygen, if available, and have victim lie down. FOR ELEC-

TRICAL SHOCK, turn off power. Remove victim; if not breathing, begin artificial respiration,

preferably mouth-to-mouth. If no detectable pulse, begin external heart massage. Call Emergency

Rescue Squad immediately.

EQUIPMENT PRECAUTIONARY LABELS

Inspect all precautionary labels on the equipment monthly. Order and replace all labels that cannot be easily read.

Page 2 Instruction 910082

Revised Nov 16182

INTRODUCTION

This manual contains operation and service information and instructions for a Hobart Induction

Motor Driven 28.5-V DC Generator Set, specification number 5651 (S-5651).

In addition to the standard unit, the manual also covers variations to the basic specifications,

which are designated by a numerical suffix to the specification number, on the nameplate.

A sub-section entitled “VARIATION,S” in Chapter 1 explains these variations, and will in-

clude any such new variations as they are added in the future.

The manual in no way is presented as a text-book on electricity or electronics. Its primary

purpose is to provide information and instructions to experienced operators, electricians

and mechanics who have never seen, nor operated this particular generator set. It is the

intent of the manual to guide and assist operators and maintenance personnel in the proper

use and care of the equipment.

Use of the manual should not be put off until a trouble or need for help develops. Read the

instructions before starting the unit. Learn to use the manual and to locate information con -

tained in it. Each page is identified in the lower outside corner by the chapter and section

number in which it appears. Each new section starts with page 1. The first figure in each

section is Figure No. 1 .

In addition to operation and maintenance instructions, the manual contains an Illustrated Parts

List in Chapter 4. A collection of manufacturer’s literature is supplied as part of the infor-

mation package.

Aug 6/“73 Introduction

Page 1

TABLE OF CONTENTS

CHAPTER/SECTION PAGE

Description/Operation

Description

q General

Special Features

Standard Unit and Variations

Physical Data

Control Box Assembly

Genera I

Control Pane I

Controls

Lights

Monitoring Instruments

Switches

Control Rheostats

Interior Pane I Assembly

Resistors

Overvoltage Module

Ammeter Shunt

Over load Re lay

Automatic Flash Relay

Load Con tactor

Voltage Regulator

Aug 6/73

1-o 1

l-l 1

1

8

Contents

Page 1

SUBXCT

Genera I

Theory of Operation

, lnstal lation,

Preparation for Use

Genera I

Inspection/Check

Installation of Unit

Genera I

Wiring

Output Cable lnstal lation

Cable Requirements

Cable Connections

Portable Mounting

Preparation for Storage

Operation

Genera I

Starting

Power Del ivery

Constant 28.5-V DC Power Delivery

Limited Current Power Delivery

Power Delivery For Helicopter Starting

Power Delivery With Manual Voltage Control 3

Contents

Page 2

Aug 6/73

CHAPTER/SECTION PAGE

l-l 8

9

l-2 1

1

1

1

1

1

1

3

3

3

3

4

l-3 1

1

1

1

1

2

2

SUBJECT CHAPTER/SECTION

TABLE OF CONTENTS (CONT’D.)

Discontinue Power Delivery

Servicing

Majntenance Inspection/Check

Genera I

Maintenance Schedule

Genera I

Maintenance Schedule Check Sheet

Time Intervals

Maintenance Procedures

Genera I

Lubrication

Genera I

Generator Bearing Lubrication

Generator Brush and Commutator Maintenance

General

Brush Service

Loss of Magnetism

Generator Controls Maintenance

Genera I

Over load Re lay

Overvoltage Module

Adjustment and Test

PAGE

l-3 3

2-o 1

2-l 1

1

1

2-2

2-3

4

4

4

4

7

1

Aug 6/‘73 Con tents

Page 3

SUBJECT CHAPTER/SECTION

Genera I 2-3

Testing the Generator Set

,

Pre-Operational Test Procedures

Operational Test

Adjusting the Generator Set

Generator Adjustment

Brushholder Adjustment

Initial Adjustment of Brushholder

Brush Spring Adjustment

Generator Controls Adiustment

Adjust Range of 700-1300 A Current Limiting

Rheostat

Adjust 400 A Current Limit Resistor

Adjust Automatic Mode Resistor

Adiust 60 Hz Operation Resistor

Trouble Shooting

Trouble Shooting Procedures

Genera I

Trouble Shooting Chart

Equipment for Trouble Shooting

Safety

Diagrams

Connections and Wiring

Contents

Page 4

3-o

3-1

PAGE

3

3

5

5

5

5

5

1

1

1

1

1

1

2

2

Aug 6/73

SUBJECT

Chart

II lustrated Parts List

Introduction

Genera I

Purpose

Explanation of Parts List

Contents

Parts List Form

“Figure-Item No. ” Column

“Part Number” Column

“Nomenclature” Column

“EFF” (Effectivity) Column

“Units per Assembly” Column

Parts List

Genera I

Parts List

Generator Set

Control Box Group

Interior Panel Group

Motor Switch Panel

Across-The-Line Switch Assembly

Motor Generator Group

Aug 6/‘73

CHAPTER/SECTION PAGE

3-l

4-o

4-l

4-2

3 thru 7

1

1

1

1

1

1

1

1

2

2

2

2

1

1

1

3

5

7

11

13

17

Contents

Page 5

CHAPTER/

SECTION

TABLE OF CONTENTS (CONT’D.)

SUBJECT CHAPTER/SECTION

Brushholder Group 4-2

Exciter Brushholder Assembly

Trailer Group

FIGURE

NUMBER

,

LIST OF ILLUSTRATION S

TITLE

PAGE

19

21

23

PAGE

NO.

l-l

l-l

l-l

l-2

l-2

2-l

2-2

2-2

2-2

2-2

2-3

2-3

1

2

3

1

2

1

1

2

3

4

1

2

Outline, MG-1028 2

Control Pane I Assembly 5

Interior Pane I Assembly 6

Across-The-Line Switch Assembly

Output Cable Connections

2

4

Ma in tenance Schedu le 2

Generator Brush Installation 3

Overload Re lay lnsta I lation 5

Over load Relay Dashpot Assembly 7

Overvoltage P.C. Board Schematic Diagram 8

Brushholder Assembly 4

Current Limiting Adjusting Resistors 6

Contents

Page 6

Aug 6/73

CHAPTER 1. DESCR IPTlON/OPERATION

SECTION 1. DESCRIPTION

1. General

The electric motor-driven aircraft energizer is a se If-contained un it powered by a

squirre I cage induction motor. 1 All of the rotating parts are mounted on a steel shaft,

supported on both ends by ball bearings. The generator and motor housings are bolted

together at the middle of the machine for ease in disassembly. The controls are all

located on top of the generator in a sheet metal control cabinet. The front cabinet

panel contains a hinged door on which are mounted the controls and instruments normally

used by the operator while the machine is in operation. This hinged door opens out

and down, to reveal the inner control panel which contains resistors, relays, etc.,

which are not used by the operator while the machine is in operation. A lifting eye

protrudes through the top of the cabinet to facilitate handling the unit with a crane

or hoist.

2. Special Features

The Model MG 1028 features a current limiting, “Soft-Start” control, recommended

by most turbine-powered aircraft and helicopter engine manufacturers, for protection

of the engine starter shear section. The inrush current may be preset to any limited

value between 700 and 1300 amperes, as recommended by the engine manufacturers.

A special 400-ampere “low” current limiting system is provided for helicopter and

small turbine starting.

3. Standard Unit and Variations

As stated previously, the standard Model MG 1028 is a self-contained, stationary unit,

identified as Specification Number 5651 (S-5651). It is equipped with two “feet”

on the generator housing, and a “pad” on the motor housing, which may be bolted

onto a base or floor configuration.

An optional type of mounting is available, as supplied for Variation 4, which provides

a portable mounting, with towing tongue for tractor towing. Shoe type brakes lock

the front wheels when towing handle is in the upright position.

Another option available as a variation is a change in the electric motor for 50-Hertz

operation at 1450 RPM. This is covered in Variation Number 3. If other variations

become available, or if changes are made, new information will be added at the end

of sections in which the information would normally be located.

Aug 6/73 l-l

Page 1

Outline MG 1028

Figure 1

4. Physical Data

A. Stationary Unit - See Figure 1

Length overa II

Width

Height overall

We’ight

Bolt-down dimensions (length)

Bolt-down dimensions (width)

(A)

(B)

K>

CD)

w

B. Portable Mounted Unit

Length overa I I

Width (outside of wheels)

54-l/4 inches (1378 mm) approx.

32-3/4 inches (832 mm)

Height overall 52-5/8 inches (1337 mm)

Weight 2000 pounds (910 kg)

Tread 28-3/4 inches (730 mm)

Whee I base 32-7/8 inches (835 mm)

Ground clearance 6-3/4 inches (172 mm)

Tires 4.80/4.00x 8

Tire pressure 60 P.S. I.

46-3/4 inches (1187 mm)

18-l/2 inches (470 mm)

44-5/8 inches (1133 mm)

1800 pounds (816 kg)

30-l/2 inches (775 mm)

15-l/2 inches (394 mm)

l-l Aug 6/73

Page 2

C. Generator

Output power rating

Vo I tage

Rated load capacity

Current limiting capability

28.5 KW

28.5 V DC

1000 A @ 100% duty cycle (1250 A for 3 min .)

700 A to 1300 A as required

400 A for helicopter starting

Operating speed 1 1750 RPM

D. Motor

Manufacturer

Type Motor volts

Motor amps

Hobart Brothers Company

Squirre I cage induction

230/460 volts

119/60 amps

E. Protective Devices

Overvoltage relay trips at 32-34 V DC, in 2-10 seconds.

Overload relay trips at 1250 A after 3 minutes.

5. Control Box Assembly

A. General

The control box is a sheet metal enclosure which houses and provides mounting

facilities for generator controls and monitoring instruments. The box is mounted

atop the generator, with a hinged instrument panel which swings down to provide

access to the interior panel, which is mounted inside the control box.

‘B. Control Panel See Figure 2

(1) Controls

The controls are all located on the front panel of the control box. The

panel contains a voltmeter, ammeter, pilot lights, generator ON/OFF

switch, motor ON/OFF switch, voltage adiustment rheostat, starting

current adjustment rheostat and current limiting switch.

(2) Lights

(a) Amber pilot light (2) d in icates that the electric motor driving the gen-

erator is running , when light is lighted.

(b) Green pilot light (1) d in icates that output load contactor is closed. See

(4) (c) below for reference to contactor control switch function.

Aug 6/73 l-l

Page 3

(3) Monitoring Instruments

(a) Voltmeter (8). Th e voltmeter is located in the upper right-hand corner

of the control panel. The purpose of the voltmeter is to indicate the

voltage generated by the energizer. The voltmeter is scaled O-50 V DC.

(b) Ammeter (6). The ammeter is in the upper left-hand corner of the control

panel. The purpose of the ammeter is to measure the amount of current that

I is being supplied by the energizer, and it will indicate only when current

is being delivered. The ammeter is scaled O-1600 amps.

(4) Switches

(4

09

(4

(4

Current Selection Switch (4). A three-position toggle switch used to select

the value of the energizer output current.

Position 1: High current, in the range of 700 to 1300 A. UP position.

Position 2: Constant DC voltage supply at 28.5 volts. CENTER position.

Position 3: Low current (400 A) for helicopter starting. DOWN position. :.,

Automatic/Manual Switch (9). A two-position toggle switch. Its function

is to select the mode of generator operation by applying either automatically

controlled (voltage regulator) or manually controlled (rheostat) excitation

to the generator fields.

Ccntactor Control Switch (10). A three-position toggle-type switch with

positions identified as CLOSE-ON-OFF. Its purpose is to connect or dis-

connect the generator output to or from the output cables to the aircraft.

The top (CLOSE) p OSI eon is spring-loaded and is used only momentarily ‘t’

for closing the load contactor. When in the center (ON ) position, the

switch conducts holding current to the load contactor to maintain it in

the closed position.

Motor ON/OFF Switch (3). A three-position toggle switch with positions

identified as START-RUN-STOP. Its purpose is to start and stop the

energizer motor. The top (START) position is spring-loaded, and is used

only momentarily for motor start-up. The switch returns to center (RUN)

position when it is given freedom to do so.

(5) Control Rheostats

(a) Starting Current Rheostat (5) is used to select the recommended starting

current for various aircraft . Output current is adjustable within a range

of 700 A to 1300 A when the current limit switch (4) (a) is in the “UP”

position.

l-l

Page 4

Aug 6/73

4’

3’

2’

6 7 8 I 7

1. Pilot light - Green 6. Ammeter

2. Pilot light - Amber 7. Manual Adjust Rheostat

3. Motor ON/OFF Switch 8. Voltmeter

4. Current Selection Switch 9. Automatic/Manual Switch

5. Starting Cur ‘r-1 ent Rheostat 10. Contactor Control Switch

Control Panel Assembly

Figure 2

(b) Manua I Adjust Rheostat (7) is used to manually control the generator

field current and thereby adjust the generator output voltage. The

rheostat is connected in the field circuit only when the automatic/

manual switch (9) is in the MANUAL position.

,9

-10

‘I

6. Interior Panel Assembly

The interior panel assembly is mounted vertically inside the control box near the

rear panel. Components are described as follows:

A. Resistors

There are five resistors, (2) (3) (4) (7) and (8) mounted on the interior panel.

Aug 6/73 l-l

Page 5

5 6 7 8 9

2-3-4

I i-------i I I I I 1 I 1 It

I I I-------\ I4 \I3

1. Voltage Regulator 8. Resistor - 20 ohm, 25 watt

2. Resistor - 4 ohm, 100 watt (outer) 9. Automatic Field Flash

3. Resistor - 20 ohm, 100 watt (center)

Relay

10. Arc Suppression Capacitor

4. Resistor - 30 ohm, 100 watt (inner) 11. Overload Relay

5. Terminal Board 12. Load Contactor

6. Overvoltage Module 13. Ammeter Shunt

7. Resistor - 100 ohm, 25 watt 14. Terminal Board

Interior Panel Assembly

Figure 3

(1) Variable resistor (2) 4 ohm, 100 watt is used to adjust field current for automatic

mode operation.

(2) Variable resistor (3) 20 ohm, 100 watt reduces exciter current for 60 Hertz

operation of electric motor.

(3) Variable resistor (4) 30 ohm, 100 watt isused to adjust generator output to

400 A for helicopter starting. This resistor is connected into the voltage regulator

signal circuit when the current selector switch (4, Figure 2) is in the 400 A

position.

l-l

Page 6

Aug 6/“/3

(4)

(5)

Resistor (7) (not adiustable) is connected across the generator output leads

and provides a very small load required to close the differential relay contacts

in the load contactor to make the contactor closing circuit functional and

allow the main contacts to close when desired.

Variable resistor (8) 20 ohm, 25 watt is connected in series with the starting

current rheostat (5, Figure 2) and is used to adjust the operating range of the

rheostat at 700 A to (1300 A.

B. Overvo I tage Modu le

The overvoltage module (6) is a protective device with solid state circuitry which

causes a normally CLOSED relay with the device to OPEN during a condition

of overvoltage in the generator output circuit. The relay contacts are connected

in the circuit which holds the load contactor closed. When an overvoltage con-

dition causes the relay to OPEN, the holding circuit is broken and the load con-

tactor opens automatically to disconnect the load from the generator. The over-

voltage module is adjusted to trip at 32 to 34-V DC, in 2-10 seconds.

C . Ammeter Shunt

The ammeter shunt (13) is connected in the generator POSITIVE output circuit.

Its function is to supply a greatly reduced current for operation of ammeter (6,

Figure 2).

D . Overload Re lay

The solenoid operated, dashpot-type relay (11) protects the generator and output

circuit against overload. The relay contacts are connected in series with the load

contactor holding circuit and are normally CLOSED when the generator is operating

normally. Th ey may be opened mechanically by action of the solenoid plunger

(or armature). A bus bar in the generator positive output circuit acts as a coil

to supply magnetic force for actuation of the plunger. An overload condition

in the output circuit provides sufficient magnetism to lift the plunger against

the retaining force of the dashpot piston and open the relay contacts, thus

breaking the load contactor holding circuit and automatically opening the

load contactor.

The resistive force of the dashpot on the plunger provides a delaying action and

prevents nuisance tripping when the generator is overloaded for short periods of

time, such as aircraft starting, etc.

The overload relay will function to open the load contactor if a load of 1250

amps continues for 3 minutes. Larger load wi II trip the relay in a much shorter

time.

Aug 6/73 l-l

Page 7

E. Automatic Field Flash Relay

The automatic field flash relay (9) and arc suppression capacitor (10) are provided

to adjust field current for the automatic mode. If the exciter output current is too

low, the relay contacts wi II remain closed until the generator voltage reaches

24 V, then the coil in the relay wil I become energized, opening the contacts and

permitting resistor (1Res) to function to control the exciter current. The arc suppression

capacitor (10) prevents the relay,contacts from arcing when opening and closing.

F. Load Con tat tor

The load contactor (12) providesa safe and convenient means of connecting or

disconnecting the generator from the load. Initial power for closing the load con-

tactor is supplied by the generator through the spring-loaded momentary contacts

of the contactor control switch (10, Figure 2).

Holding power to maintain the load cantactor in closed position passes through the

stationary contacts of the control switch, and also through the closed contacts of

the overload relay and the overvoltage module. By this circuitry arrangement, the

holding circuit is broken and the load contactor opened by either fault condition

which causes one of the protective devices to function.

G. Voltage Regulator - See Diagram 430338

(1) General

(a) The voltage regulator (1) is a solid state device designed to provide

regulation of 28-V output on self-excited, DC generators. Means are

also provided for current limiting and line drop compensation.

’ (b) The DC generator voltage is controlled by varying the average generator

field power with what is known as time-ratio control. A power transistor

in series with the field is turned cyclicly on and off, varying the average

field power by controlling the ratio of “on” time to “off” time. The

switching cycle is kept short compared to the field time constant, making

negligible the effect of the switching on the generator voltage.

The switching rate is controlled by varying, with a transistor, the rate at

which a capacitor charges to the firing voltage of a four-layer diode, in

response to the output of a reference amplifier comparing the generator

voltage with a reference voltage.

NOTE: A detailed schematic of the regulator is shown on d-iagram

430338, as applied to a separately excited DC generator.

See theory of operation, which follows.

l-l

Page 8

Aug 6/73

GENERATOR DIVISION HOw.RT BHOTtrtRS COMPAN”

(2) Theory of Operation - Transistor Ql , the series control transistor, is driven

into saturation by transistor Q2, which is biased into saturation through resistor

R8 whenever transistor Q3 is not conducting. This allows current to flow from

the exciter into the generator field through transistor Ql , and at the same time

through diode D5, transistor Q5 and resistor R5 to charge capacitor Cl at

a rate determined by the base drive of transistor Q5. When the voltage across

capacitor Cl reaches the firing voltage of 4-layer diode 02, this diode switches

from a blocking to a conducting state. When diode D2 conducts, current flows

through resistor R7 and the base to emitter junction of transistor Q4, turning

transistor Q4 on. Current then flows from the base of transistor Q3 through

resistor R6 and the col lector of transistor Q4, turning on transistor Q3, and

shunting the emitter-base junction of transistor Q2. Transistor Q2 then turns

off, turning off transistor Ql . The generator field current, sustained by the

inductance of the field, continues to flow through the path provided by diode

D4. After transistor Ql turns off, capacitor Cl discharges through 4-layer diode

D2, resistor R7 and the base of transistor Q4 until the diode current decreases

to below the value required to hold it in its conducting state. Diode D2, tran-

sistor Q4, and resistor R6 are so chosen that transistor Q4 is still saturated

at the minimum holding current of the diode. When the 4-layer diode reverts to

its blocking state, transistors Q4 and Q3, turn off, al lowing transistors Q2 and

Ql to turn on and begin the next switching cycle. The time required for capac-

itor Cl to discharge below the voltage required to sustain the 4-layer diode

current above its holding level, determines the “off” time of the Ql transistor.

The time required for capacitor Cl to charge to the firing voltage of the

4-layer diode is determined by the current passed by the transistor Q5 in response

to its base current through transistor Q6. Transistor Q6 is controlled by tran -

sistor Q8, which compares generator voltage tapped from potentiometer R13

to the voltage of reference diode Dl through its emitter and base. The time

period for which transistor Ql remains “on” between “off” periods is thus

determined by the magnitude of that part of the generator which is compared

to the reference voltage. If the generator voltage rises above the level

at which the regulator is set to regulate, the base potential of transistor Q8

decreases with respect to its emitter, which is clamped by reference diode Dl

at a fixed potential below the generator positive terminal. The current

through the transistor Q8 into the base of transistor Q6 increases, causing

the base current of transistor Q5 to increase through the collector of transistor

Q6. Transistor Q5 conducts a higher charging current to capacitor Cl,

decreasing the time required for the capacitor voltage to reach the firing

voltage of 4-layer diode D2 and the time period for which transistor Ql

conducts becomes shorter. The resulting decrease in the “on ” time of tran-

sistor Ql , with respect to its “off” time, reduces the average generator

field power to the level required to maintain generator voltage at its reg-

u lated leve I. If the generator voltage decreases be low its regulated value,

the base potential of transistor Q8 rises with respect to its emitter, resulting

in a decrease in the current of transistors Q8, Q6, and Q5. Thecharging

Aug 6/73

,

l-l

Page 9

rate of capacitor Cl decreases, resulting in longer “on” time intervals for

transistor Ql , and an increase in average generator field power to the level

required for the generator voltage to return to its rated value.

The regulating voltage may be adiusted with potentiometer R13, since the

regulator acts to keep the voltage constant between generator positive and the

slider of the potentiometer. Moving the slider towards the positive end of the

potentiometer increases generator voltage, toward the negative end decreases

generator voltage. Resistor R14 serves to bias the current in reference diode

Dl above its threshold or “knee ” current, even if transistor Q8 is biased com-

plete ly off. Line drop compensation is obtained by subtracting generator

interpole winding voltage drop from the sensed voltage through potentiometer

R9. Since the interpole winding drop and output cable drop are both pro-

portional to current, this circuit permits flat voltage regulation at the load

end of the ‘cables, by causing generator terminal voltage to rise to an amount

equal to cable drop voltage, when a load is applied.

Generator current limiting is also derived from the interpole winding voltage

drop. Part of this voltage drop is applied through resistors RlO and R 11 to the

emitter to base junction of transistor Q7. When the generator current reaches

a magnitude such that the voltage between the generator positive brush and the

slider of Rll exceeds the threshold voltage of its emitter-base diode the tran-

sistor conducts, allowing current to flow through resistor R3 into the base of

transistor Q6. This results in a decreased regulator output and a steeply dropping

generator output characteristic when the generator current exceeds a preset

value.

Provisions have been made to allow dual voltage operation of the regulator.

When the slider potentiometer R15 is connected to machine negative, the

voltage regulating range is shifted to its 14-volt range.

l-l

Page 10

Aug 6/73

SECTION 2. INSTALLATION

1. Preparation for Use

A. General

The generator set is shipped in operating condition and ready for use after inspec-

tion and checking for possible damage in shipping. Power supply cables and

I generator output cables must be suppliedand connected to the unit prior to use.

These are not supplied with the unit.

CAUTION : READ OPERATING INSTRUCTIONS IN SECTION l-3, BEFORE

OPERATING THE UN IT.

B. Inspection/Check

(1) Remove crating, blocking, banding, ties and other securing and protective

materia I.

(2) Inspect exterior for shipping damage such as broken meters, damaged sheet

meta I, etc.

C. Installation of Unit

(1) General

When installing the machine avoid, whenever possible, locations exposed

to high humidity or dust. Moisture condenses on generator parts and electrical

controls, causing corrosion which can seriously affect operation and efficiency.

Dust and dirt cause needless extra wear on all moving parts. Care should,

therefore, be taken to locate the machine so that there will be as little

opportunity as possible for excessive moisture, dust or corrosive fumes to be

drawn into the energizer.

(2) Wiring

(a) Remove the top of the control cabinet, after unscrewing the lifting

eyebolt, and removing it.

(b) Locate the connection terminals Ll, L2 and L3, on the across-the-line

switch assembly (see Figure 1) and ground (GND) stud.

(c) Check the position of the changeover (stator) links, located below the

switch assembly (above, paragraph (b) for voltage supply. See wiring

diagram in Chapter 3 of this manual.

Aug 6/73 l-2

Page 1

; QO

_... _.I.. --..-..e..I.. - ._.-._. 2 Y . *OHAH, B”“,,<, “S COMP&NI “0 c‘ +, 9. s,,+c

NOTE: Links are positioned in a vertical arrangementfor 230-V power supply;

and in horizontal arrangement for 460-V supply.

CAUTION : BE SURE THAT THE POWER SUPPLY IS CONNECTED THROUGH

A FUSED DISCONNECT SWITCH (FURNISHED BY THE CUS-

TOMER) AND THAT THE WIR IN G TO THE MOTOR IS OF

SUFFICIENT SIZE TO CARRY THE LOAD. CHECK THE FOLLOW-

ING DATA,:

Motor Size: 50 HP

Approx. Line Fuse Rating:

230 V 400 Amp

460v 200 Amp

Min. Size Wire - Rubber Insulation:

230 V #3/o

460v #3

CONNECTION TERMINALS

Ll, L2 AND L3

GROUNDING

/

STUD

Across-The-Line Switch Assembly

Figure 1

l-2 Aug 6/‘73

Page 2

(d) Power supply cables enter the cabinet through holes near the top, on the

right-hand end panel of the cabinet (facing instrument panel). Pass the

cables through the holes before connecting onto the terminals, to allow

the top of the control cabinet to be replaced in position.

D. Output Cable Installation

Units are normally supplied without a generator-to-aircraft cable.

(1) Cable requirements

Cable length is determined by the customer’s requirements. It is recommended

that the cable be no longer than 40 feet. The cable should be two conductor

with lug-type terminals on one end and an AN-2551 plug connector on the

other end.

Recommended conductor size for 28.5-V DC and continuous rated amperage

(1000 A) is #4/O size.

NOTE: Some operators may wish to add a second cable assembly with

MS-25019 plug connector for starting aircraft such as Jetstar

and Sa bre I iner .

(2) Cable connections - See Figure 2

Connect the two conductors to the bus bar connections on the backside of the

interior pane I. Use capscrews, washers and nuts, and tighten securely to the

connections.

Store the cable assembly on hangers at rear of the control cabinet.

NOTE: Output cables exit from the cabinet through elongated holes in

left-hand end panel of the cabinet (facing instrument panel).

E. Portable Mounting

Mount the energizer on the portable mounting as follows:

(1) Remove the wooden skid from under the energizer unit.

(2) Lift the energizer with a hoist until the rear axle assembly, with wheels

can be fitted under the feet of the generator housing.

(3) Securely fasten the rear axle to the feet of the generator housing.

Aug 6/73 l-2

Page 3

rPOSITIVE CONNECTION

-NEGATIVE

CONNECTION

Output Cable Connections

Figure 2

(4) Locate the front axle, with wheels, under the front mounting plate on the

motor housing. Attach the front axle to the plate by means of the bolt, nut,

and cotter key provided.

2. Preparation for Storage

When a generator set is to be stored or removed from operation, special precautions

should be taken to protect the internal and externa I parts from rust and corrosion.

A. The unit should be prepared for storage as soon as possible after being removed from

service.

B. Storage should be in a building which is dry and which may be heated during

winter months.

C. Moisture absorbing chemicals are available for use where excessive dampness is

a problem, however, the unit must be completely packaged and sealed if moisture

absorbing chemicals are to be effective.

1-2

Page 4

Aug 6/73

SECTION 3. OPERATION

1. Genera I

This section contains information and instructions for the safe and efficient operation

of the generator set. Operating instructions are presented in a step-by-step sequence

of procedures to be followed in supplying 28.5-V DC to an aircraft.

NQTE: Read ALL of the operating instructions before attempting to operate

the equipment.

2. Startina

A. To start the electric motor-driven energizer, place the MOTOR, 3-position

switch in START (Up) position.

NOTE: This toggle switch is momentary contact type switch. Hold it UP

until motor starts, and then release it to the RUN position. Amber

light (2, l-l, Figure 2) should glow.

B. The armature of the machine should rotate in the direction indicated by the

arrow on the front panel below the nameplate. lf it does not, place the motor

switch in STOP (Down) position, throw the disconnect switch (see CAUTION,

Section 2, page 1, under C (2).

C. To reverse the direction of rotation, reverse the connections of any two of the

incoming power lines, either at the disconnect switch or at the motor switch.

(See Figure 1 and text under (2) Wiring, Section 2, page 1.)

3. Power De livery

There are several methods of power delivery including (1) Constant 28.5-V DC Voltage,

(2) Limited Current (Soft-start), (3) Helicopter Starting and (4) Manual Voltage Con-

trol. Each mode of operation will be described below.

NOTE: Refer to l-l, Figure 2 for reference to item call-out numbers, if not

otherwise identified.

A. Constant 28.5-V DC Power Delivery

Output voltage to the aircraft (power consuming end-item) will be automatically

regulated at approximately 28.5-V DC by the voltage regulator. (Ref. Section

l-l, Figure 3, item 1)

(1) Place the current selection switch (4) in CONSTANT VOLTAGE (Center)

position for this mode of operation.

Aug 6/73 l-3

Page 1

(2) Place the automatic-manual switch (9) in AUTOMATIC (Up) position.

(3) Check to make sure that the aircraft (power consuming end-item) is ready

to receive power from the energizer.

NOTE: Current selection switch (4) and fie Id rheostat (7) are non -functiona I

in the constant voltage mode.

(4) <Place the MOTOR switch (3) in START position, and hold momentarily

until pilot light (2) glows amber. Release switch to RUN position.

(5) To apply power to the aircraft, close the load contactor control switch (10)

(Generator) by holding the switch in CLOSE (Top) position momentarily, until

indicator light (1) glows green. Release switch and a I low it to return to ON

(Center) position. Light (1) should continue to glow, indicating that the load

contactor is closed, and that power is available at the generator output.

B. Limited Current Power Delivery

Not all aircraft engine starters require the same cranking current. In the limited

current mode, the current output is adiustable from 700 A to 1300 A, by means

of the current selection switch.

(1) Place the current control switch (4, l-l, Fig. 2) in CURRENT LIMITING (Up)

position.

(2) Place the automatic-manual switch (9, l-l, Fig. 2) in AUTOMATIC (Up)

position.

NOTE: A voltage value of approximately 28.5-V DC should be indicated

on the voltmeter.

(3) Check to make sure that the aircraft is in ready condition to receive power

from the generator.

(4) Place the MOTOR switch (3) in START position, and hold it momentarily

until pilot light (2) glows amber. Release switch to RUN position.

(5) Adiust starting current rheostat to current required, within the range of 700 A

to 1300 A. Set to maximum current desired.

(6) To apply power to the aircraft, follow instructions in A, (5), above.

C. Power Delivery for Helicopter Starting (400 A)

Helicopter and small turbine starting requires a low current limiting capability

not possible by using the current limiting rheostat (5). For helicopter starting,

proceed as follows:

l-3 Aug 6/73

Page 2

(1) Place automatic-manual switch (9) in AUTOMATIC (Up) position.

(2) Place the current limiting switch (4) in 400 A (Down) position. In this switch

position, the current limiting rheostat (5) is by-passed and the maximum out-

put of the generator is limited to approximately 400 A.

(3) To apply power to the aircraft, follow instructions in A, (5), above.

D, Power Delivery With Manual Voltage Control

This mode of operation is recommended for generator testing, or for emergency

use in case of voltage regulator trouble only. For manual control of generator

output voltage, use normal operating procedures, except:

(1) Place automatic-manual switch (9) in MAN UAL position.

(2) Use the rheostat (7) to manually regulate voltage at 28.5-V DC. Turn knob

clockwise to increase voltage, and counterclockwise to reduce voltage.

4. Discontinue Power Delivery

A. Place load contactor control switch (10) in OFF (Down) position. Light (1)

should go off to indicate load contactor has opened, and power is no longer

available at the energizer output cables.

B. Place motor switch (3) in STOP (Down) position.

C. Disconnect cable plug from the aircraft receptacle and store cable on hangers

at rear of control cabinet.

Aug 6/73 l-3

Page 3

l-3

Page 4

Aug6,'73

CHAPTER 2. SERVICING

SECTION 1. MA INTENANCE INSPECTION/CHECK

1. Genera I

To make certain the generator set is always in good operating condition,

spected, maintained and lubricated regularly and systematically.

WARN ING: STOP OPERATION AT ONCE IF A SER IOUS OR POSSIBLY

DANGEROUS FAULT IS DISCOVERED.

it must be in-

2. Maintenance Schedule

A. General

A periodic maintenance schedule should be established and maintained. A suggested

schedule is provided in Figure 1. It may be modified as required to meet varying

operating and environmental conditions.

B. Maintenance Schedule Check Sheet

It is strongly recommended that the customer use a maintenance schedule check

sheet. The check sheet will provide a record of maintenance operations performed

and may also serve to improve scheduling for a specific operation.

C . Time Intervals

The schedule is based on both hours of operation and calendar intervals. These

two interva Is are not necessarily the same. The calendar period is included to

make certain services are performed regularly when equipment is being operated

less than normally. Perform all services on a “whichever comes first” basis.

CAUTION: WHEN CLEANING THE UNIT, DO NOT USE A HIGH PRESSURE

SPRAY WITH SOAP OR DETERGENT, OR STEAM CLEANER ON

THE GENERATOR OR OTHER ELECTRICAL EQUIPMENT. IF

SOAP ENTERS THE GENERATOR BEARING, ITS LIFE WILL BE

SHORTENED. DETERGENT AND STEAM MAY ALSO PENETRATE

OTHER E LECTR ICAL EQUIPMENT AND CAUSE CORROSION,

RUST, SHORTING, ETC.

Aug 6/73 2-l

Page 1

Check indicating I ight

Check operation of all instruments,

meters, etc.

Check generator brushes for length,

clean I iness, and free operation

Check commutator for smoothness

and cleanliness

Check overload relay dashpot

Clean the entire unit

Check overload protection

Check overvoltage protection

Check all wiring and connections

10 Hrs.

or

Daily

X

X

100 Hrs.

2 ;ks.

X

Maintenance Schedule

Figure 1

LOO Hrs.

I Go.

400 Hrs.

2 Go.

X

X

t 300 Hrs.

6’;o.

X

X

X

X

2-l

Page 2

Aug 6/73

SECTION 2. MAINTENANCE PROCEDURES

1. Genera I

A suggested Maintenance Schedule was provided in Section 1 of this Chapter. This

Section covers maintenance in more detail where necessary.

WARN ING: STOP OPERATION Af ONCE IF A SERIOUS OR POSSIBLY SERIOUS

FAULT IS DISCOVERED.

2. Lubrication

A. General

Proper lubrication is one of the most important steps in good maintenance procedure.

Proper lubrication means the use of correct lubricants and the adherence to the

proper time schedule.

B. Generator Bearing Lubrication

There are only two places on the generator unit which require lubrication. These

places are the two end bearings which support the armature shaft. These bearings

are packed withenough grease when the machine leaves the factory to last 6 to

8 months under most severe use. After this initial period, the manufacturer suggests

that the bearings be lubricated twice yearly.

(1) Procedure

(a) To lubricate the bearings, remove the bearing caps from both motor and

generator housings. Remove the three bolts that hold the bearing caps

in place.

(b) Remove as much old grease as possible, and wash out the bearing and cap

with kerosene or warm diesel fue I. DO NOT use gasoline.

(c) Fill clean bearing cap about l/3 full, and fill the bearings 50 to 75%

full of recommended bearing grease. See paragraph (3) be low. Place cap

in position and tighten bolts securely.

(2) Cleanliness

DO NOT inspect or lubricate the bearings more often than every six months.

Always wipe area clean around the bearing cap before removing it.

Aug 6/73

__. _,_,

2-2

Page 1

(3) Lubricant

Ordinary cup grease is not a satisfactory lubricant for ball bearings. Use only

a clear, non-corrosive, heat-resistant, medium-bodied grease recommended for

ball bearings. Such a grease, H B-354, is available from Hobart Brothers in

l- and 5-pound containers. DO NOT use a graphite lubricant.

3. Generator Brush and Commutator Maintenance

A. General

The only maintenance service required for the generator will be brush replacement,

commutator clean ing , etc.

B. Brush Service

(1) Cleaning

If inspection reveals that brushes are gummy or sticking in the brushholders, they

should be removed and cleaned. Clean both the brushes and brushholders. Use

a good, SAFE, commercial cleaner. DRY ALL PARTS THOROUGHLY. Be sure

brushes can move freely in brushholders.

WARN IN G: DO NOT USE A FLAMMABLE SOLVENT. DO NOT USE STEAM

CLEANER, OR SOAPS AND DETERGENTS UNDER PRESSURE.

(2) Replacement

Brushes for this application are l-3/4 inches long when new. They should be

replaced when worn to one-half their original length, or 7/8 inch.

(4

04

(4

(4

(4

2-2

Page 2

Remove pigtail attaching screw.

Move brush spring (1, Fig. 1) aside and remove old brush (3).

Check new brushes before installation. Size must be 3/4 x 1 x l-3/4

inches long.

Move brush spring aside and install new brush.

NOTE: Check position of brush pigtail and install so that pigtail

is on the forward side of the brush.

Check the clearance between brush and brushholder. The brush should

move up and down freely in the holder, yet without excessive side-to-side

or fore-and-aft movement.

Aug 6/73

1 . Spring

2. Pigtail

3. Brush

4. Nut

5. Spring mounting

adapter

6. Wrench

6 4’

Generator Brush lnsta I lation

Figure 1

(f) Connect the pigtail. A single screw attaches two brush pigtails.

(g) Repeat steps (a) through (f) for other brushes.

(3) Brush seating

When replacing brushes, it is important that they be carefully fitted to the

commutator ring. The seating stone method of brush seating is recommended

for this installation.

Seating stones are fine-grain, abrasive blocks made especially for brush

seating. When applied to the commutator, fine particles from the stone

drift under the brush and shape its face to the same curve as the commutator.

(a) Start the motor and operate the generator with no power output.

(b) Hold the stone against the commutator immediately behind the brushholder

so that stone particles will be carried directly under the brush. Steady the

stone by holding it against the brushholder.

(c) Seating may be speeded up by applying extra pressure on the brush.

WARN IN G: EXERCISE CARE TO AVOID IN JURY BY THE ROTAT-

IN G EQUIPMENT OR E LECTR ICAL ‘SHOCK,.

Aug 6/73 2-2

Page 3

(d) Use only dry compressed air to blow out any grit or foreign material.

CAUTION: DO NOT APPLY A FULL LOAD UNTIL BRUSHES HAVE

RUN-IN FOR APPROXIMATELY ONE HOUR AT 300 TO

400 A LOAD.

(4) Brush springs

Refer to Section 2-3, Page 4, Para. 3, A, (3) for brush spring adjustment instruc-

tions.

(5) Commutator cleaning

One of the best ways of cleaning the commutator is to use a piece of clean,

hard-woven canvas, attached to, or folded cn a wooden stick. Hold the

canvas against the rotating commutator until dirt and smudge are removed.

Another effective method of cleaning and smoothing the commutator is the

use of a flexible abrasive block especially manufactured for commutator

cleaning. When held against the revolving commutator, the block wil I

quickly remove deposits of dirt and grease.

Operate the generator at 300 to 400 A load for approximately one hour to

allow a film to form on the commutator after cleaning.

C . Loss of Magnetism

In isolated cases, the exciter loses its residual magnetism in shipment, with the

result that no voltage is generated. This condition is corrected by raising the exciter

brushes and applying an outside source of DC voltage, not in excess of 110 V, for a

few seconds, to the exciter brushes of opposite polarity. This sets up a magnetic

field which leaves enough residual magnetism to cause the exciter to build up by

itself when the brushes are again lowered on the commutator. If, after the outside

DC voltage has been applied, the exciter still fails to generate voltage, again

raise the brushes and reverse the outside voltage through the exciter brushes.

4. Generator Controls Maintenance

A. General

The overload relay dashpot (2, Fig. 3) is the only component of the control system

which requires periodic inspection and maintenance.

B. Overload Relay

The entrance of water into the dashpot or the use of improper fluid may cause operating

troubles requiring disassembly and repair of the dashpot assembly. The foIlawing

instructions include repair procedures in the recommended sequence of steps.

2-2 Aug 6/73

Page 4

(1) Disassemble

(a) Hold the dashpot and unlatch the spring clamp (4) by prying with a screw-

driver to swing the clamp forward. Lower and remove the complete dash-

pot assembly.

(b) Lift the core (l), cover (2),

an assembly.

and valve plate (6) out of the dashpot (3) as

(c) Pour the dashpot fluid into a clean glass container and inspect for signs

of water.

NOTE: Moisture may condense in the dashpot to form water which

wil I cause corrosion of the valve plate and dashpot.

CONTACTS

BUS BAR

(28.5 V OU

PLUNGER

DASHPOT

Over load Re lay lnstal lation

Figure 2

Aug 6/73

TPUT)

2-2

Page 5

(2) Inspection

Inspect the valve plate (6) and the dashpot (3) for evidence of corrosion. Discard,

if corroded, and replace with new parts. Observe the position of the two valve

plate covers. One is diamond shaped and retains two steel balls (5). This cover

should not be disturbed. The other plate serves to cover the valve plate by-pass

holes, and MUST be positioned to completely COVER and CLOSE the holes.

(3) Assemble *

(4

(b)

(4

(4

(e )

( f )

Pour a sufficient quantity of new fluid into the dashpot to cover the

circular ridges in the bottom. Use a silicon fluid witha viscosity rating

of 100 centistokes at 25OC.

Approved fluids are:

Dow-Corning No . 200 ( 100 ten tistokes)

Allen-Bradley No. 810-N9B, Series A

Allen-Bradley No. X-106518

NOTE: Allen-Bradley numbers indicate different container sizes.

Install the valve plate (6) and core (1) as an assembly. Make certain that

the valve plate “bottoms” in the dashpot.

Add fluid until the surface of the fluid is leve I with the tops of the three

cylindrical projections on top of the valve plate. Actuate the piston a

short distance up and down to expel any air trapped below the plate. Re-

check the fluid level and add fluid if required.

Install the dashpot cover (2).

Make certain the valve plate (6) is “bottomed” in the dashpot and measure

the height that the core protrudes above the rim of the dashpot. The core

must extend 3/4 inch above the dashpot rim. Increase the height by turn-

ing the core in a counterclockwise direction. Decrease the height by turn-

ing the core in a clockwise direction. Turn the core a full turn at a time

and be sure the lock spring (7) is seated in the valve plate stud groove when

the adjustment is completed.

Position the dashpot assembly in the overload relay and lock in place with

the spring clamp (4).

Aug 6/“73

Rev. Apr 26/74

I

1. Core (plunger)

2. Cover ,

3. Dashpot

4. Spring clamp

5. Steel balls

6. Va Ive plate

7. Lock spring

2

LEVEL

Overload Relay Dashpot Assembly

Figure 3

C. Overvoltage Module

The overvoltage relay contacts are part of the solid state module, and in case of

malfunction, the printed circuit board should be replaced. (Module-PC Over-

voltage Board 389522A is listed in Parts List. )

To test overvoltage module:

(1) Supply fused and filtered DC power, 20 to 40 volts (adiustable), to plus (+)

and minus (-) terminals on P.C. Board.

(2) Connect ohmmeter across terminals P and T, Figure 4.

(3) Adjust (Pl) potentiometer to trip relay at 32 volts in 2-10 seconds. No trip

at 31 volts.

(4) With 35 volt input, check for trip time to be approximately 1 second.

NOTE: See Trouble Shooting Chart, Chapter 3, Section 1, for test on

overvoltage relay.

Aug 6/73 2-2

Page 7

R2 I.2Kn

PI IKll

R3 4.7Kr

--

1 cI+Tg 1 I I

R6 22Kn

. -lA 2N-3903

4 .W F

R8 270n 02 TD----J

RIO 15Odl.

Overvoltage P. C. Board Schematic Diagram

Figure 4

.c.;

2-2

Page 8

Aug 6/73

SECTION 3. AD JUSTMEN T/TEST

1. Genera I

These adjustment and test procedures are most applicable to testing and adiusting the

generator set after major repair, replacement of parts, long storage, etc.

2. Testing the Generator Set ,

A. Pre-operationa I Test Procedures

Perform the following checks, tests, and operations before starting the unit.

(1) Connect cables from the generator output terminals to a load. Use cables

of the same size and length as those to be used in service, preferably size 2/O,

and not more than 30 feet long.

(2) Make a general inspection of all wiring and connections to find any obvious

incorrect wiring, loose wires, and loose or shorted terminal lugs.

(3) Set manual control rheostat (7, Sect. l-l, Fig. 2) to MIN IMUM position *

(4) Set automatic-manual switch (9, Sect. l-1, Fig. 2) to MANUAL position.

(5) Check panel lights (1 and 2, Sect. l-l, Fig. 2).

B. Operationa I Test

(1) Start electric motor as described in Chapter 1, Section 3, Page 1, Sub-section

2.

(2) Check and record manual rheostat range which should be approximately 2 V DC

minimum to 49 V DC maximum as observed on voltmeter (8, Sect. l-l, Fig. 2).

Reset rheostat at 28.5-V DC.

(3) Place contactor switch (10) in top CLOSE position momentarily. Release, and

allow switch to return to center ON position. Load contactor should CLOSE

and indicating light (10) should glow green.

(4) If brushes have been replaced, proceed as follows:

(a) Use brush-seating stone to seat brushes.

(b) Apply a load of 300 to 400 A and allow brushes to “run-in” for a minimum

of 1 hour.

Aug 6/73 2-3

Page 1

(5) Adjust brushholder to give 27.5 to 28.5 V at 750 A load when no-load voltage

is set at 28.5 with manual control rheostat. (See Para. 3, A, (1) for adjustment

procedures. )

(6) Check overload relay trip time at 1250 A. Should trip in approximately 3

minutes. (See Sect. 2-2, Page 4.)

(7) Check overvoltage relay. Should trip at 32 to 34 V DC. (See Sect. 2-2,

Page 7.)

(8) Place automatic-manual switch (9, Sect. l-l, Fig. 2) in AUTOMATIC

position. Adjust rheostat on voltage regulator to 28.5 V DC (see attached

voltage regulator instructions).

(9) Place current-limiting rheostat (5, Sect. l-l, Fig. 2) in MAXIMUM position

and current-limiting selector switch (4) in 700-1300 A position.

(10) With a 900-1000A I d oa applied, turn current-limiting rheostat counterclockwise

until ammeter indicates 700 A. The knob pointer should be at 700 A on the dial.

If not, set the movable pointer to 700 A on dial.

(11) Check current limiting at 700, 1000, and 1300 A.

(12) Place current-limiting switch (4, Sect. l-l, Fig. 2) in 400 A position. Check

current limiting at 400 A for helicopter service.

(13) Check voltmeter accuracy. Error must not exceed 2% full scale.

(14) Check ammeter accuracy. Error must not exceed 4% full scale.

3. Adjusting the Generator Set

A. Generator Adjustment

The brushholder assembly and the brush hold-down springs may require adiustment if

the generator is disassembled, or if parts are replaced.

WARNING: DO NOT MAKE ADJUSTMENTS WHEN THE GENERATOR IS RUNNING.

(1) Brushholder adiustment

The brushholder assembly is mounted in a machined, circular seat in the rear of

the generator housing. The brushholder mounting ring is held in the seat by clamps

and the entire brushholder assembly may be rotated when the clamps are loosened.

To adjust, proceed as follows:

2-3 Aug 6/73

Page 2 Rev. Apr 26/74

(a) With generator running at no load and automatic-manual switch (9, Sect.

l-l, Fig. 2) in MAN UAL position, use manual control rheostat (12) to

adiust voltage to 28.5 V.

(b) Apply a load of 750 A and check output voltage. If voltage is 27.5 to

28.5 V, the brushholder is properly adjusted. If voltage is below 27.5

V, or above 28.5 V, adjustment is required.

(c) Stop generator and scribe a mark on the brushholder mounting ring, and

on one of the seat bars to determine a starting point for adjustment.

(d) Loosen brushholder clamping screws (2, Sect. 2-3, Fig. 1) and rotate the

brushholder (1) in the direction of armature rotation to REDUCE voltage,

or opposite the direction of rotation to INCREASE voltage. Do not rotate

the brushholder more than l/8 inch without rechecking voltage. Tighten

clamping screws (2) before starting generator.

(e) Start generator and repeat steps (a), (b), (c), and (d) as required until a

satisfactory adjustment has been made.

(f) Be sure clamping screws (2) are securely tightened at conclusion of

adjustment.

(2) Initial adjustment of brushholder

In the event that the generator is disassembled and the brushholder assembly is

removed, locate the brushholder as follows:

(a) Rotate armature so that an armature slot is directly under an interpole

piece. Carefully observe and trace the wires which lead from the winding

in the slot to a commutator segment (5, Sect. 2-3, Fig. 1). Rotate the

brushholder ring (1) so that a row of 4 brushes is directly over this segment.

Tighten brushholder clamping screws (2).

N OTE: Exercise care in tracing the armature to commutator wire

because the wires run at an angle and not directly to a

commutator segment . It may be possible to detect yellow

paint marks on the armature slot and the commutator riser

which were used to position the brushholder originally. If

these marks can be found, it will make brushholder adjust-

ment easier.

(b) Make final adjustment in accordance with Para. 3, A, (l), above.

(3) Brush spring adiustment

Recommended spring pressure is 18 to 30 ounces measured along an imaginary

line which passes through the center of the brush and the center of the com-

Aug 6/73 mutator. 2-3

Page 3

Brush spring pressure is very difficult to measure accurately. Since spring

pressure is not critical as long as it is sufficient to prevent brush bouncing

and not great enough to cause excessive mechanical, brush wear, it is recom-

mended that springs be adjusted by feel. Adjust as follows:

(a) Make certain that the brush is free to move in the holder.

(b) Lift the spring away from the brush with the finger. If the spring is exerting

firm, but not excessive pressure on the brush, adjustment is not required.

(c) If spring pressure feels weak on the brush, loosen nut (Sect. 2-2; 3, Fig. 7)

and turn spring adapter (5) toward the brush (arrow direction). Tighten

nut (4).

(d) If spring pressure feels excessive, loosen nut (4) and turn adapter (5) away

from brush (opposite arrow direction).

NOTE: The adapter (5) must be held in its new adiusted position while

tightening (or loosening) the nut (4).

RMATURE OTAT ION

1. Brushholder mounting

2. Clamp screw

3. Clamp

4. Seat bar

5. Commutator segment

ring

Brushholder Assembly

Figure 1

Aug 6/73

4. Generator Controls Ad justmen t

Various generator controls may require adjustment following replacement of parts, repair,

etc. Adjustment procedures are listed as follows:

A. Adjust Range of 700-1300 A Current Limiting Rheostat

The resistor (3RES) (8, Seot. 2-3, Fig. 2) is used to adjust the current limiting

I range of the rheostat (5, Sect. l-l, Fig. 2) to 700 to 1300 A. Adjust as follows:

(1) To increase the current range value, move slider (9, Sect. 2-3, Fig. 2)

to right.

(2) To decrease current range value, move slider (9) to the left.

(3) Recheck voltage range after each adjustment.

NOTE: When adiustment is completed as indicated by the ammeter,

it may be necessary to readjust the rheostat (5, Sect. l-l,

Fig. 2) pointer so that it will point to the same amperage

value as indicated by the ammeter.

B. Adjust 400 A Current Limit Resistor (4RE S) (I nner of three stacked resistors)

This resistor (5, Sect. 2-3, Fig. 2) is used to adjust the 400 A current limiting

system so that the maximum generator output power will be 400 A when the current

limiting selector switch (4, Fig. 2) is in 400 A position, for helicopter starting.

The normal initial setting of the slider (6, Sect. 2-3, Fig. 2) on this resistor

is l/8 inch (3.2 mm) from the top end.

(1) Move the slider (6, Sect. 2-3, Fig. 2) DOWN to increase current.

(2) Move the slider (6) UP to decrease current output.

C. Adjust Automatic Mode Resistor (2RES) (Outer of three stacked resistors)

This resistor performs the function of limiting current in the generator field circuit.

Setting is in mid-position for 2 ohm resistance.

D. Adiust 60 Hz Operation Resistor (1RES) (Center one of three stacked resistors)

This resistor is factory-set for 10 ohms, in the exciter field circuit. Used when

generator set is in use on 60 Hertz power.

Aug 6/73 2-3

Page 5

1. Automatic mode resistor (2RES)

2. Slider

3. 60 Hz operation resistor (IRES)

4. Slider

5. 400 A current limiting resistor (4RE S>

6. Slider

7 8: Non-adjusting resistor (5RE S) 700 to 1300 A current limiting resistor (3RES)

9. Slider

10. Interior panel

Current Limiting Adiusting Resistors

Figure 2

Aug 6/73

2-3

&age 6

CHAPTER 3. TROUBLE SHOOTING

1.

SECTION 1. TROUBLE SHOOTING PROCEDURES

Genera I

2.

3.

4.

Trouble shooting is an orderly process of checking and eliminating possible causes of

trouble until the exact cause ‘of a trouble is found. As a rule, the best place to start

looking for the cause of a trouble in a circuit is at the source of power. Continue

testing and checking the circuit, step-by-step, in an orderly manner, until the cause

of trouble is located. See connection and schematic diagrams.

Trouble Shooting Chart

A. Description

The trouble shooting chart lists information under three headings:

(1) Trouble, symptom, and condition

(2) Probable cause

(3) Test, check, and remedy

B. Use of the Trouble Shooting Chart

Read the trouble symptoms and conditions before proceeding to causes and remedies.

With problem known, locate trouble in TROUBLE, SYMPTOM and CONDITION

column, and check PROBABLE CAUSE and TEST, CHECK and REMEDY columns.

Equipment for Trouble Shooting

A good quality multi-scale voltohmmeter is the only instrument required for trouble

shooting. At least two “iumper” leads with “alligator”, or similar clips, will be

required. The 12-V, engine electrical system may be used for a 12-V DC power

source.

Safety

WARNING: EXERCISE EXTREME CARE TO AVOID CONTACT WITH ELECTRICAL

CIRCUITS AND REVOLVING EQUIPMENT WHICH COULD CAUSE

SERIOUS IN JURY IF TOUCHED WHEN TROUBLE SHOOTING OR

OPERATING THE EQUIPMENT.

Aug 6/73 3-l

Page 1

5. Diagrams

A schematic diagram of the generator set is provided, following the Trouble Shooting

Chart. This diagram can be very helpful in trouble shooting. Components shown in the

diagram are identified by symbols (or item names in some instances). A legend appearing

on the diagram identifies each electrical symbol by its full item name. For example,

the symbol, “OV” identifies the overvoltage relay, and “VM” identifies the voltmeter. ,

6. Connections and Wiring

Before condemning any electrical component, check all connections and wiring which

could affect its operation. In many instances a component may be non-functional simply

because it is not receiving power because of a loose connection or a poor ground. In

most cases throughout the trouble shooting chart, it will be assumed that connections

and wiring have been checked.

A Connection Diagram follows the Trouble Shooting Chart, also. Consult it for reference

to power supply and output.

3-1

Page 2

Aug 6/“73

GENERATOR DIVISION “OB*HT “ROIU~RS COMPI\N”

TROUBLE JYMPTOM

AND CONDITION PROBABLE CAUSE TEST, CHECK, AND REMEDY

GENERATOR AND ( >NTROLS

1. Generator will

not build-up-volt

age I

Automatic-manua

control switch in

the AUTOMATIC

position. Motor

running normally.

A. Defective field flash relay

,

B. Defective automatic-

manual switch

C. Defective voltage reg-

u lator

A. Replace relay (FFR)

NOTE: If voltage does not build-up

by replacing the relay above, the

trouble may be in the generator, or in

the voltage regulator and excitation

circuit.

B. Place automatic-manual control

switch (9, l-l, Fig. 2) in

MANUAL position. If voltage will

now build-up, it proves that the

generator is good, and that the

trouble is in automatic section of

automatic-manual switch, or in the

voltage regulator. Return switch

to AUTOMATIC position. Connect

a jumper lead across the contacts

on the automatic side of the switch

If voltage will now build-up, re-

place the automatic-manual control

switch.

Z. If voltage would not build-up when

automatic contacts of switch were

jumpered (in step B, above) trouble

is in the voltage regulator. Re-

place the voltage regulator.

3

Aug 6/73 3-l

Page 3

GENERATOR DIVISION HOBART BROI,ILRS COMPPlN”

TROUBLE, SYMPTOM,

AND CON D ITION PROBABLE CAUSE

GENERATOR AND CONTROLS (CONTINUED)

TEST, CHECK, AND REMEDY

2. Generator will not A. Defective automatic- A. Connect a jumper lead across

bui Id-up voltage manual switchI MANUAL contacts of switch

(1s). If generator will now

Automatic-manual bui Id-up voltage, replace

control switch in switch (1s) (9, l-l, Fig. 2).

MANUAL position. If voltage will NOT build-up,

Motor running proceed to step B.

normally.

B. Defective manual control B. Connect a jumper lead across the

rheostat (1RH) manual control rheostat. If gen-

erator will now build-up, re-

place the rheostat (9, l-l, Fig.

2). If not, proceed to step C.

C. Defect in generator C. If generator would not build-up

voltage during steps 2, A and B

above , it indicates the generator

is defective. Check for open

circuited shunt fie Ids.

3. Load contactor will A. Defective resistor (SRES) A. The load contactor requires a

not close when gen - slight load on the output circuit

erator (load con - to close the differential contacts

tactor) switch (10, and allow the ccntactor to be

l-l, Fig: 2) is closed. Resistor (!5RE S) provides

placed in CLOSE this load when output cables are

position. Motor not connected to a load. Check

running, NO load this resistor (Sect. l-l, Page 7)

applied to output and replace if defective.

cable.

B. Defective contactor con- B. Momentarily connect a jumper

trol switch (4s) lead between terminals 1 and 2

on the control switch (4s). If

the load contactor closes momen,

tarily, replace switch (4s) (10,

l-l, Fig. 2).

C. Defective load contactor

U-C)

C. If load contactor will not close

when control switch (4s) is

jumpered, it is, likely that the

con tactor is defective .’

3-l

Page 4

Aug 6/73

HOBART ;MOTOR GENERATOR DIVISION

HORAHT BROTHt “S COMI’AN”

TROUBLE, SYMPTOM

AND CONDITION PROBABIE CAlJSF TFST; CHFCK; AND RFMFDY

GENERATOR AND CONTROLS (CONTINUED)

4. Load contactor A. Defective control switch A. Connect a jumper lead between

OPENS as soon (4S) ’ termina Is 4 and 5 on the control

as control switch switch (4s). If contactor will now

is released from remain closed after initial closing,

the CLOSE replace the control switch (4s)

position. (10, l-l, Fig. 2).

B. Overload relay (20L) B. Connect a jumper lead across the

defective over load re lay (20L) contacts.

If contactor will now remain

closed, replace overload relay

(20L) (Sect. 2-2, pages 4-7).

CAUTION: DO NOT OPERATE THE GENERATOR SET TO DE LIVER

POWER WHEN AN,Y PROTECTIVE DEVICE IS JUMPERED.

C. Overvoltage relay (OV)

defective

C. Connect a jumper lead between

terminals “T” and “P” on the over-

voltage relay (OV). If con tactor

will now remain closed, replace

overvoltage module (Sect. 2-2,

page 7).

D. Load contactor (LC) defec- D. If a fault was not found in steps

tive 4, A, B or C above, the load con-

tactor is defective. Replace load

contactor (LC) (12, l-l, Fig. 3).

5. Load contactor A. Contactor opening could A. Resume operation and closely ob-

opens during have been normal due to an serve ammeter and voltmeter for

power de I ivery overload or overvoltage evidence of overload and over-

run. condition. voltage. If contactor opens when

it is known that there were no over

load or overvoltage conditions,

proceed to step B.

B. Overload relay (20L) defec- B. Oi I in the overload relay dashpot

tive may be low, allowing the plunger

to operate too freely. Check dash.

pot in accordance with instructions

in Sect. 2-2, pages 4-7. Also

Aug 6/73 3-l

GENERATOR DIVISION HOEWRT BROIHLRS COMPAN”

ROUBLE,SYMPTOM,

AND CONDITION PROBABLE CAUSE TEST, CHECK, AND REMEDY

GENERATOR AND CONTROLS (CONTINUED)

5. (Continued) B. (Continued)

C. Overvoltage reiay (OV)

defective

B. check overload relay contacts.

C. Check overvoltage relay by

operating the machine under loac

and controlling voltage manually

Start with a low voltage (25.0 V

DC) and gradually increase unti I

the relay functions to open the

load contactor. If relay trips at

less than 32 V DC, replace relay

and return old relay to factory

for service.

D. Load contactor defective D. If no fault was found in checks

B and C above, the load con-

tactor is at fault. Replace load

contactor (LC) (12, l-l, Fig. 3)

5. Generator voltage A. Defective voltage regula- A. Use automatic-manual switch

will not build up to tor (9, l-l, Fig. 2) to change to

normal operating MAN UAL control. If normal

voltage in AUTO- operating voltage (28.5 V DC)

MATIC control mode. can be selected with manual

control, replace the voltage

regulator module.

7. Generator voltage A. Defective voltage regula- A. Switch to MANUAL control.

builds too high in tor If normal operating voltage can

AUTOMATIC con- be selected with manual control,

trol . replace the voltage regulator.

3. Output current can - A. Defective current I imiting A. Change current limit control

not be limited by rheostat (lRH), or defective switch (2s) to 400 A current

operating current or improperly adjusted limit position. If current is now

limit rheostat when resistor (3RE S). limited to 400 A, check rheostat

selector switch is in and resistor. (See Sect. 2-3,

700 to 1300 A sub-sect. 3, B, (1) for resistor

position. adjustment.) Replace parts as

required.

3-l

Page 6

Aug 6/73

GENERATOR DIVISION HOBART BROlHfRS COMPAN”

TROUBLE, SYMPTOM] I AND CGNDITION 1 PROBABLE CAUSE 1 TEST, CHECK, AND REMEDY

GENERATOR AND

8. (Continued)

9. Output current

is not limited

when current

selector switch

is in 400 A

position.

CONTROLS (CONTINUED)

I B. Defective voltage regulator

4. Resistor (4RES) is defective

or improperly adjusted

B. Defective voltage

regulator

B. If current is not limited in eithc

700-1300 A or 400 A switch

position, a defective voltage n

ulator is indicated. Replace at

return old regulator to the fact,

for service.

A. Change current selector switch

700 to 1300 A limiting position

current can be limited in this

position, adjust or replace resi:

(4RES). (See Sect. 2-3, sub-s

3, B (2) for resistor adjustment.

Replace parts as required.

B. If current is not limited in eithc

selector switch (2s) position,

replace voltage regulator and

return old regulator to factory

service.

II

Aug 6/73 3-l

Page 7

3-l

Page 8

Aug 6/73

CHAPTER 4. ILLUSTRATED PARTS LIST

SECTION 1. INTRODUCTION

1. Genera I

The illustrated Parts List identifies, describes, and illustrates main assemblies, and

detail parts of a 28.5-volt, lOOO-ampere, 28.5-KW electric motor-driven Aircraft

Energizer, manufactured by Motor Generator Division, Hobart Brothers Company,

Troy, Ohio 45373. The unit is identified by Specification Number (SPECS) 5651.

2. Purpose

The purpose of the list is to provide parts identification and descriptive information to

maintenance and provisioning personne I for use in provisioning, requisitioning, purchas-

ing and issuing of spare parts.

3. Exolanation of Parts List

A. Contents

The parts list contains a breakdown of the equipment into assemblies, subassemblies,

and detail parts. All parts of the equipment are listed except:

(1) Standard h ar d ware items (attaching parts) such as nuts, screws, washers,

etc., which are available commercially.

(2) Bulk items such as wire, cable, sleeving, tubing, etc., which are also

commercially available.

(3) Permanently attached parts which lose their identity by being welded,

soldered, riveted, etc., to other parts, weldments, or assemblies.

B. Parts List Form

This form is divided into five columns. Beginning at the left side of the form

and proceeding to the right, columns are identified as follows:

(1) “FIGURE-ITEM NO. I’ Column

This column lists the figure number of the illustration applicable to a

particular parts list and also identifies each part in the list by an item

number. These item numbers also appear on the illustration. Each item

number on an illustration is connected to the part to which it pertains by

a leader line. Thus the figure and item numbering system ties the parts

list to the illustration and vice versa.

July 6/‘73

TM-297

4-l

Page 1

(2) “PART NUMBER ‘I Column

All part numbers appearing in this column are Hobart numbers. If a Hobart

number has not been assigned to a part, “NO NUMBER” will appear in the

column and a vendor number will be listed in the NOMENCLATURE column.

(3) “NOMENCLATURE ” Column

The item identifying name appears in this column. The indenture method is used

to indicate item relationship. Thus components of an assembly are listed directly

below the assembly and indented one space. Sizes, ratings, or vendor part

numbers may also appear in this column.

(4) “EFF” (Effectivity) Column

This column is used to indicate applicability of parts when two or more models

of equipment are covered by the parts list. Code letters are used to indicate

parts which are used only on a certain model or models. Parts in the list are

coded as follows:

Uncoded parts are usable on all machines.

Parts coded “A” are usable onbasic Specs 5651 only.

Parts coded “B” are usable on Specs 5651, Var. 3 only.

Parts coded “C” are usable on Specs 5651, Var. 4 only.

(5) “UNITS PER ASSEMBLY” Column

This column indicates the quantity of parts required of an assembly or subassembly

in which the part appears. This column does not necessarily reflect the total

used in the complete end item.

4-l July 6/73

Page 2 TM-297

SECTION 2. PARTS LIST

1. General

Illustrations appear on left-hand pages, and parts lists appear on opposite right-hand

pages for the convenience of the user.

July 6/73

TM-297

4-2

Page 1

4-2

Page 2

Generator Set

Figure 1

July 6/“73

TM-297

. . 0”

@

ZMOTOR GENERATOR DlVlSfON : :: 0 . HOflARl BHOTHtHS COMPAN” “0 d *< 4. e,,\ $

FIGURE PART

ITEM N 0. NUMBER

NOMENCLATURE UN ITS

1234567 EFF A!&

l- s5651 GENERATOR SET, 28.5 V DC,

1000 AMPS, 60 HZ A

S565 1 -V3 GENERATOR SET, 28.5 V DC,

11000 AMPS, 50 HZ B

s5651 -v4 GENERATOR SET, 28.5 V DC,

1000 AMPS, TRAILER MOUNTED C

1 No Number . CONTROL BOX GROUP (For

Details See Fig. 2)

2 No Number . MOTOR GENERATOR GROUP

(For Details See Fig. 6)

3 W-4460(67C) . TRAILER GROUP (For Details

See Fig. 9)

Ju I y 6/73

TM-297

REF

REF

REF

4-2

Page 3

;MulOR GENERATOR DIVISION HOClAHl BHOIHLRS COMPAN”

Control Box Group

Figure 2

July 6/73

TM-297

SMOTOR GENERATOR DIVISION

N OME NC IATURE

FIGURE PART

ITEM NO. NUMBER 1234567

2- No Number

1 481096

2 481083

3 481099

4 No Number

CONTROL BOX GROUP (For NHA

See Fig. 1)

. PANEL, COVER

. PANE L, FRONT ASSEMBLY

PANE L, H INGED ASSEMBLY

: PANE L, INTER IOR GROUP

(For Details See Fig. 3)

5 481093

6 481088

7 481091

8 5C w-3405

9 3 89535- 1

10 W-8061A-11

11 W-8063A-3

12 480911

. PANEL,SIDE, LEFT,ASSEMBLY

. PANEL, SIDE, RIGHT, ASSEMBLY

. PANEL, REAR, ASSEMBLY

. EM, LIFTING

. ROPE, SUPPORT

. AMMETER

. VOLTMETER ’

13 400400

14 402159

15 403 189

16 H F-25 18-7

17 W-97 12-7

18 HF-2518-11

19 402855

20 403189

21 AAW-83%

2? 16DA-2162

23 DWP-1815

24 382818

25 W-l 1250

26 403336

27 DW-4701A-0

28 DWP-1186-O

29 7J -422

30 w-10051-4

31 w-10051-5

32 401864

33 A-98

. PANEL, SWITCH, MOTOR

ASSEMBLY (For Details See Fig. 4)

. SWITCH, TOGGLE, AUTO, MAN.

. RHE OSTAT, VvLTAGE

. SWITCH, TOGGLE, GENEKATOR

. LIGHT, PILOT, GREEN

RHE OSTAT, CURRE NT

: LIGHT, PILOT, AMBER

. SWITCH, TOGGLE, CL-CV

. SWITCH, TOGGLE, MOTOR

. RHEOSTAT, KNOB

. RHEOSTAT, KNOB

. STRAP, GROUNDING

. SCREW, FASTENING, HINGED PANEL

. WASHEK, SOUTHCO

. RING, LOCKING SWITCH

. HANGER, CAt3lE

. BRACKET, CLAMP, CABLE

. CIAMP, CABLE, MAIN STARTING

. CLAMP, WIRE

. CLAMP, WRE

. NAMEPLATE, IDENTIFICATION

. IABE L, ROTATION

NHA NEXT HIGl+K ASSEMBLY

UN ITS

E FF A&

RE F

1

1

1

PEF

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

2

2

4

2

2

2

1

1

1

1

July 6/73

TM-297

4-2

Page 5

r- -

\.

Inter ior Panel Group

Figure 3

4-2

Page 6

July 6/73

TM-297

FIGURE PAR T

ITEM NO. NUMBER

3- No Number

1

2 t

3

4

480903

w-454 1 -c

W-4541-D

APY-34

W-2974-D

5 W-2974-N

6 W-2974-M

7 400589-3

8 401556

9 403763- 1

10 3 89522A

11 400589-5

12 FW-2 13 1

13 6FW-2845

14 6FW-2087A

15 6FW-2085

16 6FW-1799

17 6FW-2714

18 Y-10

19 DWP-1653

20’ 480904

21 389466

22 6FW-2091

23 40 1564-2

24 401566-l

25 A-25

26 480993

27 481087

28

29

30

430336

6FW-2537

6FW-2532

6FW-2536

NHA

July 6/‘73

TM-297

NEXT H IGHER ASSEMBLY

NOMENCLATURE

1234567

PANEL, INTERIOR GROUP (For

NHA See Fig. 2)

. PANE L, INTER IOR ASSEMBLY

. ‘. RESISTOR, 20 OHM, 25 W

. . RESISTOR, 100 OHM, 25 W

. . BRACKET, MTG., RESISTORS

. . RESISTOR, 4 OHM, 100 W

(OUTER)

. . RESISTOR, 20 OHM, 100 W

(CENTER)

. . RESISTOR, 30 OHM, 100 W

(INNER)

. . BLOCK, TERMINAL

. . MOUNT, SHOCK

. . WASHER, FIBER

. . BOARD, P. C. OVERVOLTAGE

. . BLOCK, TERMINAL

. . RE LAY, OVER LOAD

. . BUS, POSITIVE TERMINAL RELAY

. . RE LAY, HARTMAN, A791M

. . BUS, SHUNT TO REV. CURRENT

RELAY

. . SHUNT, 50 MV

. . BUS, TERMINAL TO SHUNT

. . SPACER

. . BUS, CON TACTOR

. . PANE L, INTER IOR

. . BRACKET, RELAY

. . PLATE, TERMINAL, NEGATIVE

. . HOUSING, SOCKET,

CONNECTOR

. . TERMINAL, SOCKET

. . WASHER, FIBER

. . LABE L, OPERATING FREQlIN CY

. BRACKET, MOUNTING, INTERNAL

PANEL

. REGULATOR, VOLTAGE ASSEMBLY

. RESISTOR, CURRENT REGULATOR

f . BUS, TERMINAL BLOCK TO

RESISTANCE

. . RESISTOR, ELEMENT, CURRENT

UN ITS

per EFF ASSY

REF

1

1

1

2

1

1

1

1

3

3

1

1

1

1

1

2

1

1

1

8

1

4-2

Page 7

4-2

Page 8

July 6/73

TM-297

FIGURE PART

ITEM NO, NUMBER

3- 31

32

33 t 3 87725

34 16DA-4004A-3

35 16DA-4052-O

36 16DA-4253-1

37 W-10051-8

38 16DA-3731

6FW-2535

6FW-2929

480590

NOMENCLATURE UN ITS

1234567

. . BUS, CABLE TO RESISTANCE

BUS, BANK RESISTOR

,: KIT, RE LAY, PLUG-IN, 24 V.

ASSEMBLY

. . BRACKET, MTG., SOCKET,

RE IAY

. . RELAY, PLUG-IN, 24 V.

. . SOCKET, RELAY

. . RETAINER, SPRING, RE LAY

. CLAMP, WIRE, PLASTIC

. CAPAC ITOR, 15 MFD, 200 V

EFF A&

1

July 6/73

TM-297

4-2

Page 9

0 0 ii

\ 7 0 A

0

\Q

/

Motor Switch Panel Assembly

Figure 4

4-2

Page 10

6

July 6/73

TM-297

FIGURE PART

ITEM NO. NUMBER

4- 4809 11

1 480922

2 402949

3 I 402948

4 430114-6

9

402947

400589-l

400533

25MS-302-4

357678

402677

10 No Number

11 36 1922

12 No Number

13 35753 1

14 16DA-4252-16

15 400651

16 400670

17 CW-811

18 404083- 1

19

20

21

42517

400828-l

AW-367

NOMENCLATURE

1234567

PANEL, SWITCH, MOTOR,

ASSEMBLY (For NHA See Fig. 2)

.

I.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

PANEL, MTG., MOTOR iWITCH

NAMEPLATE, L3

NAMEPLATE, L2

SWITCH, ACROSS LINE ASSEMBLY

(For Details See Fig. 5)

NAMEPLATE, Ll

BLOCK, TERMINAL

NAMEPLATE, GROUND

ELEMENT, HEAT, OVERLOAD

BLOCK, OVERLOAD, ASSEMBLY

. SWITCH, MICRO SPNC., 250

TAB

. SCREW, #6-32 x 3/8, SET,

SOCKET, OVAL POINT

. BAR, ACTUATING

. SCREW, #6-32 x 5/8, SET, SKT.,

HD., ST.

BLOCK, OVERLOAD

&SE, SLOW BLOWING

HOLDER, FUSE

TRAN SFORMER , CONTROL

STRAP, CONNECTING

TERMINAL, R IN G TONGUE,

#8 WIRE, #8 STUD

INSULATION, SLEEVING, FIBER-

GLAS, YELLOW, SIZE 0

TIE, WIRE, PLASTIC

SPACER, PANE L

NHA NEXT HIGHER ASSEMBLY

July 6/73

TM-297

UN I TS

Per

EFF ASSY

REF

1

1

1

1

6

4-l/2"

3

4

4-2

Page 11

V

\

\

100 Amp Across Line Switch Assembly

Figure 5

4-2

Page 12

FIGURE

ITEM NO.

5-

1

2 I

3

4

5 DATA 1330A

6 1 OOMS-6

7 1 OOMS-8

8 1 OOMS-79

9 1 OOMS-9A

10

11

12

13

14

15

16

17 430076-2

18 200MS- 116

19 1 OOMS-466

20 1 OOMS-238A

21 430047-O

22 lOOMS-14

23 25MS-323

24 25MS-324

25 1 OOMS-449

26 W-l 1245-8

27 25MS-309

28 lOOMS-137

29

NHA

PART

NUMBER 1234567

430114-6

430111

50MS-28

lOOMS-141

43 0048

1 OOMS-358

SWITCH, 100 AMP, ACROSS LINE,

ASSEMBLY (For N HA See Fig. 4)

PANEL, MOLDED, ACROSS LINE

1. SWITCH

. HOLDDOWN, COIL

. YOKE, MOVABLE, MAGNETIC,

SA

. STOP, MOVABLE, MAGNETIC,

YOKE

. COIL, NVR

. WASHER, MAGNETIC, BLOWOUT

COIL

. CYLINDER, BLOWOUT COIL

ASSEMBLY

. . CYLINDER

. . INSULATOR

. SPRING, MAGNETIC BLOWOUT

COIL

lOOMS-122-1

lOOMS-146

1 OOMS-122-0

50MS-300

1 OOMS-336 - 1

50MS-472

430113

430075-2

. HOLDER, ARC SH IE LD

. SHIELD, ARC

. HOLDER, ARC SH IE LD

. STRAP, CONNECTING

. MOUNT, CONTACT, STATIONARY

. SUPPORT, SINGLE BEARING

. INSULATOR, BETWEEN PHASE

. SHAFT, ARMATURE & CONTACT

ASSEMBLY

. . CONTACT, MT. SA

f . . CON TACT

. . . LEAD, PIGTAIL

. . SHAFT, ARM ASSEMBLY

. . INSULATION , SHAFT, ARMA-

TURE

. . CLAMP, SHAFT, ARMATURE

. BRACKET, MTG., MICRO SWITCH

I ARM, LEVER

. SWITCH, MICRO

. WASHER, FLAT, 3/8 BRS

. INSULATION , PANEL

. YOKE, STATIONARY, MAG-

NETIC, SA

. LEAD, CLAMP 5CW-529

NEXT HIGHER ASSEMBLY

NOMENCLATURE UN ITS

Per EFF ASSY

REF

1

2

1

6

3

1

1

3

3

3

3

2

3

1

3

1

3

1

1

1 ’

July 6/73

TM-297

July 12/76 Kevised

4-2

Page 13

4-2

Page 14

FIGURE PAR T

ITEM N 0. NUMBER

N OMEN CLATURE

1234567

5- 30 No Number . TUBING, VINYL-FLEX, 4000

I 31 33 32 200MS-116 lOOMS-132 25MS-156 ,. . . MOUNT CONTACT BUS, JUMPER

Ott 19/76 Revised

July 6/73

TM-297

UN ITS

Per EFF ASSY

REF

1

3

3

4-2

Page 15

I i

P

( : -

;

FIGURE PART

ITEM NO. NUMBER 1234567 EFF

6- No Number

1 6FW-5734- 1

MOTOR GENERATOR GROUP (For

NHA See Fig. 1)

. ARMATURE, 28.5V, 1000 A., DC

, ELEC. ASSEMBLY

2 I

3

4

5

6

W- 10072-8

DW-882A

DW-883

5B-48

6FW-858B

. BEARING, BALL, SINGLE ROW,

RADIAL

. CAP, BEARING

. GASKET, CAP, BEARING

. NUT, l-9/16-14

7 430278

8 6FW-2442

. BRUSHHOLDER GROUP (For Details

See Fig. 7)

. BUSHING, LEAD

. COIL, INTERPOLE, 1000 A, 6 POLE,

GEN.

9 6FW-1896

10 DATA 1888- 1

11 6FW-1501-2

W-10126-6

AW-720B

6FW-2453

. COVER, LOUVER, GENERATOR

. COIL, FIELD, SHUNT, GENERATOR

HOUSING, GENERATOR, 600 A.,

‘6 POLE, ASSEMBLY

. INSULATION

12

13

. . WRAPPING, POLEPIECE EXCITER

. . COLLAR, INSULATING, GENERA-

TOR

14

15

16

6FW-4033

6FW-2770

6FW-889

. . INSULATOR, FLUX RING TO POLE

PIECE, GENERATOR

. . INSULATION, 7” PLUG HAT,

WRAPPER, GENERATOR

. . INSULATION, INTERPOLE,

WRAPPER, GENERATOR

17 6FW-2771

18 6FW-2455

19 6FW-2769

. . INSULATION, 7” PLUG HAT,

TOE, GENERATOR

POLEPIECE, INTERPOLE, GEN-

- ERATOR

. POLEPIECE, PLUG HAT, GEN-

ERATOR

20 6FW-1488

21 430015-l

. GUARD, OUTLET, AIR, ASSY

. HOUSING & STATOR, MOTOR

ASSEMBLY

22 DW-4414 . BRUSHHOLDER ASSEMBLY I

EXCITER (For Details See Fig. 8)

23 6FW-220 . COVER, LOUVER, EXCITER END

24 DATA 491 . COIL, FIELD, EXCITER

25 BW-97 . POLEPIECE, EXCITER

NHA

July 6/73

TM-297

NEXT HIGHER ASSEMBLY

NOMENCLATURE UN ITS

Per ASSY

REF

1

1

4

6

1

6

1

REF

4

12

36

6

6

12

6

6

1

1

1

1

1 SET

4

4-2

Page 17

F8

I

i. ..-. .-. _. ___ . . . .

Brushholder Group

Figure 7

July 6/73

TM-297

--

a e z QD

$MOTOR GENERATOR DIVISION e

> G % *. ,,,I‘++

FIGURE

ITEM NO.

PART

NUMBER

7- No Number

6FW-858B

1 t 6FW-864

2 W-10855-4

3 6FW-862

4 AW-740

5 6FW-5719

6 AW-1156

7 AW-734

8 AW-638C

9 W-799F-#113

10 AW-667A

11 A W-732

12 A-25

13 BW-107

14 AW- 1470

15 6FW-1480

16 24FW-23

17 24FW-27

18 SAY-84

19 W-9234-4

20 W-9234-2 1

2i W-9234-l 8

22 6FW-3351

NOMENCLATU?E

1234567

BRUSHHOLDER GROUP (For NHA

See Fig. 6)

. BR USHH OLDER ASSEMBLY,

’ 6 POLE

. . MOUNT, BRUSHHOLDER

. . CONDENSER,.25 MFD, 100 V

. . PLATE, BRUSHHOLDER, SUPPORT

. . SPACER, BRUSHHOLDER

. . SPACER, BRUSHHOLDER

. . PLATE, GUIDE & FINGER,

BRUSHHOLDER, ASSEMBLY

. . . PLATE & GUIDE, BRUSHHOLDER

. . . WASHER, SPR IN G AD JUSTIN G

. . . SPR IN G, TEN SION

. . . BUSHING, LEVER SCW,

TENSION

. . . FINGER, BRUSHHOLDER, SA

. . WASHER, FIBER

. . BUSH IN G, BRUSHHOLDER

. . BRUSH , COPPER GRAPH ITE

. . BRACE

. . BUS BAR

. . BUS

. . SPACER

. LEAD, BRUSHHOLDER

. LEAD, BRUSHHOLDER

. LEAD, BRUSHHOLDER

. STRAP, POSITIVE, ASSEMBLY

NHA NEXT HIGHER ASSEMBLY

UN ITS

Per EFF ASSY

REF

1

1

6

6

30

12

24

1

1

1

1

1

24

12

24

6

6

3

3

1

1

1

2

July 6/‘?‘3 4-2

TM-297 Page 19

Exciter Brushholder Assembly

Figure 8

4-2

Page 20

July 6/73

TM-297

FIGURE PAR T

ITEM NO. NUMBER

8- DW-4414

1 AW-671

2 AW-626

3 AW-63 1

4

5

6 AW-696

7 AW-638C

8 AW-667A

9 400562-5

10 AW-634

11 4DW-423

AW-630

W-l 0753-4

AW-700

NOMENCLATURE

1234567

BRUSHHOLDER, EXCITER ASSEMBLY

(For NHA See Fig. 6)

. MOUNT, BRUSHHOLDER

. BUSH IN G, BRUSHHOLDER

‘. RING, OUTER, EXCITER,

BR USHHOLDER

. RING, INNER, EXCITER,

BRUSHHOLDER

. CON DENSER

. PLATE, MTG., BRUSHHOLDER

ASSEMBLY

. . PLATE & GUIDE, BRUSHHOLDER

SA

. . WASHER, SPRING, ADJUSTlNG

. . BUSH IN G, LEVER, TENSION

. . SPRING, TENSION

. . FINGER, BRUSHHOLDER, SA

. BRUSH , CAR BON

NHA NEXT HIGHER ASSEMBLY

July 6/‘73

TM-297

UN ITS

Per EFF ASSY

REF

1

4

1

1

2

4

4-2

Page 21

1) z .z QD

;MOTOR GENERATOR DIVISION .

-, ,’ HOB*“I 8H”iHLRS COMPAN” 5 Q. 8.11 8

Trailer Group

Figure 9

4-2 July 6/73

Page 22 TM-297

FIGURE PART

ITEM NO. NUMBER

9-

1

2

3

NOMENCLATU?E

1234567 EFF

W-4460(67C)

35566 1

DW-6641

cw-773

5CW-5125

5CW-3466

5C W-5083

DW-3860

5CW-3208

TRAILER GROUP (For NHA See Fig. 1) C

. AXLE, REAR ASSEMBLY C

WHEEL, PNEUMATIC, 4:00 X 8

I* (Geneva Metal Wheel Co., Geneva,

Ohio. DC305-1 KW224-D16. 3”xl”

Durex Bearing Axle) C

. CAP, HUB C

. AXLE, FRONT, ASSEMBLY C

. . AXLE & TONGUE, ASSEMBLY C

. . YOKE & FIFTH WHEEL, ASSY C

. . SHAFT, YOKE PLATE C

. . SHOE, BRAKE C

UN ITS

Per ASSY

REF

1

NHA

July 6/73

TM-297

NEXT HIGHER ASSEMBLY

4-2

Page 23

4-2

Page 24

July 6/73

TM-297

-

r 23

0 O

R 46

0 V.

AC

(4

60

V C

ON

N.

SHO

WN

) 50

UR

60

HZ.

IN

PUT

POW

ER

- SW

IN

D

(

r”

0

5RES

26.5

I!

DC

OU

TPU

T PO

WEf

L JU

MPE

R

INST

ALL

ED

FOR

50

H

Z.

OPE

RA

TIO

N

EI

REM

OVE

D

FOR

60

H

Z.

OPE

RA

TIO

N.

LEG

END

AM

BER

IN

DIC

ATI

NG

LI

GH

T (M

OTO

R

RU

NN

ING

) IO

L A

MM

ETER

, G

ENER

ATO

R

2OL

AM

MET

ER

SHU

NT,

16

00A

.. 50

MV.

ov

CA

PAC

ITO

R,

0.1

MFD

, 10

0 V.

IP

L2-7

CA

PAC

ITO

R,

0.25

M

FD.

IOO

V.

REI

CA

PAC

ITO

R,

1.5

MFD

, 20

0 V.

RE

G

CO

MPO

UN

DS

IRES

EXC

ITER

A

RM

ATU

RE

2RES

FIEL

D

FLA

SH

REL

AY,

A

UTO

MA

TIC

3R

ES

EXC

ITER

FI

ELD

4R

ES

GEN

ERA

TOR

FI

ELD

5R

ES

FUSE

, SL

OW

B

LOW

ING

, 2A

IR

H

GRE

EN

IND

ICA

TIN

G

LIG

HT

(LO

AD

O

N)

2RH

G

ENER

ATO

R

AR

MA

TUR

E IS

INTE

RPO

LES

2s

LOA

D

CO

NTA

CTO

R

3s

MO

TOR

SW

ITC

H

4s

MO

TOR

ST

ATO

R

(460

V

CO

NN

. SH

OW

N)

IT

VM

IA

AM

AS

l.2C

AP

3-6C

AP

9CA

P

CO

MP

EXC

FFR

IFLD

2FLD

IFU

IG

GEN

INT

LC

MS

MTR

OVE

RLO

AD

, M

OTO

R

OVE

RLO

AD

R

ELA

Y,

GEN

ERA

TOR

OVE

RVO

LTA

GE

REL

AY

CO

NN

ECTO

R,

VOLT

AG

E R

EGU

LATO

R

RES

ISTA

NC

E BA

NK

REG

ULA

TOR

, VO

LTA

GE

RES

ISTO

R,

20

OH

M,

100

WA

TT

RES

ISTO

R,

4 O

HM

, 10

0 W

ATT

RES

ISTO

R,

20

OH

M,

25

WA

TT

RES

ISTO

R,

30

OH

M,

100

WA

TT

RES

ISTO

R.

100

OH

M,

25

WA

TT

RH

EOST

AT,

C

UR

REN

T

RH

EOST

AT,

VO

LTA

GE,

M

AN

UA

L F

A.0

SU

P 6

FFP

SWIT

CH

, A

UTO

MA

TIC

-MA

NU

AL

a’P‘

r*.lc

LI

t

11

3 C

O”.

‘il

,SL,

(

&PC

, To

D.I.

ll.l

s,o<

‘1

. A

5

SWIT

CH

, C

UR

REN

T LI

MIT

PH

OTC

CTI

V~ Il

.dilS

Y SW

ITC

H,

MO

TOR

ST

AR

T-ST

OP

CM

AN

GC

Li

i( CO

””

SWIT

CH

, C

ON

TAC

TOR

O

N-O

FF

.~

v.,

lpi”

,I “i

l,E

*..,

s*i,t

x ::b

irl

TRA

NSF

OR

MER

, C

ON

TRO

L (4

6OV

CO

NN

. SH

OW

?&

‘:I

.::,‘A

- ’

’ /-

‘8,’

VOLT

MET

ER

/-- ---

w 22;

:A:

P :-----

- -----7

R2 1.2KA

--

330n 31/qw.

K7 IOKA

RS 47on

R8 27OA D2

RIO 15On

L

:: Dl, D2 Pl

If:

:: R2 R3 R4 R5, R6

%I RV RlO

LEGEND

CAPACITOR 1.5/35 CAPACITOR SO/25 DIODE POTENTIOMETER 1K OHM, l/2 WATT TRANSISTOR 2N-3903 TRANSISTOR 2N-3904 TRANSISTOR PROGRAMMABLE UNIJ-2N-6027 RESISTOR 330 OHM, 3-l/4 WATT RESISTOR 1200 OHM, l/2 WATT RESISTOR 4700 OHM, l/2 WATT 1

RESISTOR 5600 OHM, l/2 WATT RESISTOR 22K OHM, l/2 WATT RESISTOR 10K OHM, l/2 WATT RESISTOR 270 OHM, l/2 WATT RESISTOR 470 OHM, l/2 WATT RESISTOR 150 OHM. l/2 WATT RELAY ZENER 22 VOLT E, 22