Solenoid Valve PRODUCT MANUAL YT-720 SERIES · Solenoid Valve PRODUCT MANUAL YT-720 SERIES YT-720S YT-720D Rotork YTC Limited VERSION 1.11 . Solenoid Valve YT-720 Series Product Manual

Solenoid Valve PRODUCT MANUAL YT-720 SERIES

YT-720S YT-720D

Rotork YTC Limited

VERSION 1.12

Solenoid Valve YT-720 Series Product Manual

Ver. 1.12 2

Contents

1 Introduction .................................................................................................................................... 3

1.1 General Information for the users ............................................................................................ 3

1.2 Manufacturer Warranty ............................................................................................................. 3

1.3 Explosion Proof Warning .......................................................................................................... 4

2 Product Description ...................................................................................................................... 5

2.1 General ..................................................................................................................................... 5

2.2 Main Features and Functions ................................................................................................... 5

2.3 Label Description...................................................................................................................... 5

2.4 Product Code ........................................................................................................................... 6

2.5 Product Specification ............................................................................................................... 6

2.6 Certifications ............................................................................................................................. 7

2.7 Parts and Assembly ................................................................................................................. 7

2.8 Product Dimension ................................................................................................................... 9

3 Operating Logic ........................................................................................................................... 10

3.1 YT-720S ................................................................................................................................. 10

3.2 YT-720D .................................................................................................................................. 11

4 Installation .................................................................................................................................... 12

4.1 Safety and Installation Tips .................................................................................................... 12

4.2 Tools for installation ................................................................................................................ 12

5 Connection – Power .................................................................................................................... 14

5.1 Safety ..................................................................................................................................... 14

5.2 Coil body and Rotator ............................................................................................................ 15

5.3 Connection of terminal ........................................................................................................... 16

6 Connection - Air ........................................................................................................................... 17

6.1 Safety ..................................................................................................................................... 17

6.2 Supply Pressure Condition ..................................................................................................... 17

6.3 Piping Condition ..................................................................................................................... 17

6.4 Connecting piping of YT-720S ............................................................................................... 18

6.5 Connecting piping of YT-720D ............................................................................................... 19

7 Maintenance ................................................................................................................................. 20

8 Troubleshooting and repair ........................................................................................................ 21


Ver. 1.12 3

1 Introduction

1.1 General Information for the users

Thank you for purchasing Rotork YTC Limited products. Each product has been fully inspected after

its production to offer you the highest quality and reliable performance. Please read the product

manual carefully prior to installing and commissioning the product.

➢ Installation, commissioning, and maintenance of the product may only be performed by trained

specialist personnel who have been authorized by the plant operator accordingly.

➢ The manual should be provided to the end-user.

➢ The manual can be altered or revised without any prior notice. Any changes in product ’s

specification, design, and/or any components may not be printed immediately but until the

following revision of the manual.

➢ The manual should not be duplicated or reproduced for any purpose without prior approval from

Rotork YTC Limited, Gimpo-si, South Korea.

➢ In case of any other problems that are not stated in this manual, please make immediate contact

to Rotork YTC Limited.

➢ This product is an accessory of the control valve, so please make sure to read the applicable

instruction manual of the control valve or other equipment prior to installation and operation.

1.2 Manufacturer Warranty

➢ For the safety, it is important to follow the instructions in the manual. Manufacturer will not be

responsible for any damages caused by user’s negligence.

➢ Any modifications or repairs to the product may only be performed if expressed in this manual.

Injuries and physical damages caused by customer’s modifying or repairing the product without

a prior consultation with Rotork YTC Limited will not be compensated. If any alterations or

modifications are necessary, please contact Rotork YTC Limited directly.

➢ The warranty period of the product is (18) months from the date of shipment unless stated

otherwise. Date of shipment can be checked by providing the LOT NO. or SERIAL NO. to us.

➢ Manufacturer warranty will not cover products that have been subjected to abuse, accidents,

alterations, modifications, tampering, negligence, misuse, faulty installation, lack of reasonable

care, repair or service in any way that is not contemplated in the documentation for the product,

or if the model or serial number has been altered, tampered with, defaced or removed; damages

that occurs in shipment, due to act of God, failure due to power surge, or cosmetic damage.

Improper or incorrectly performed maintenance will void this limited warranty.

➢ For detailed warranty information, please contact the corresponding local Rotork YTC Limited

office or main office in South Korea.


Ver. 1.12 4

1.3 Explosion Proof Warning

Please ensure the unit is being used and installed in conformity with local, regional, and national

explosion proof certified environment.

➢ YT-720 is Explosion proof construction for internal pressure.

For detail information, refer to “2.6 Certifications”

➢ Explosion proof type of cables and gaskets should be used, when explosion gases are present

at the installation site. Please make sure that the sealing has been done completely.

➢ Keep cover tight while circuits are alive.

➢ Power should be turned off completely when opening product’s cover. When opening the cover,

ensure that there is no power remaining in any electrical parts nearby.

➢ Three ring terminals are already assembled on the power connection. Be sure to use this ring

terminal when connecting wires.

➢ There are two ground terminals inside and outside of the product. Use the supplied ring terminal

even when wiring to the ground terminal

➢ There is risk of explosion due to electro-static charge. Static electricity charge may develop

when cleaning the product with a dry cloth. It is imperative to avoid static electricity charge in the

hazardous environment. If cleaning the surface of the product is needed, must use wet clothes.


Ver. 1.12 5

2 Product Description

2.1 General

The YT-720S (3 Way) and YT-720D (5 Way) series of explosion-proof solenoid valves are designed

to output the pneumatic pressure input to the valve by DC or AC voltage signal (YT-720D: Switch

output port direction)

2.2 Main Features and Functions

➢ Designed to be flameproof enclosure.

➢ Manual switch allows to carry-out operational test even when there is no voltage power

connected.

➢ It is convenient to attach the power cable from the field as the conduit entrance can be rotated

(265 degrees). In addition, the coil body itself can rotate 360 degrees, making installation easy.

➢ In case of YT-720D, valve body is operated by pneumatic operation instead of spring return type,

so operation is very smooth with high durability regardless of supply pressure.

➢ With Namur type design, it can be attached directly to the actuator.

➢ Product surface is anodized and therefore, corrosion resistance is excellent.

2.3 Label Description

Fig. L-1: Sticker label

• MODEL : Indicates the model number and additional symbols.

• EXPLOSION PROOF : Indicates certified explosion proof grade.

• RATING : Indicates allowable voltage and current.

• AMBIENT TEMPERATURE : Indicates allowed explosion proof ambient temperature range.

• AIR SUPPLY : Indicates allowed supply air pressure range.

• LOT NO. : Indicates unique lot number.

• YEAR.MONTH : Indicates manufactured year and month.

※ Precautions

Be careful not to apply volatile solvent (hardener of instant adhesive, acetone, WD-40, etc.) to

the sticker nameplate. Printed contents may be erased.


Ver. 1.12 6

2.4 Product Code

YT-720 1 2 3 4

1 Valve type S :

D :

3 Way

5 Way

2 Air Connection Type P :

N :

Rc 1/4

1/4 NPT

3 Power Source

1 :

2 :

3 :

AC 110V

AD 220V

DC 24V

4 Air Pressure 1 :

2 :

3 :

0 ~ 0.4 MPa (3 Way)

0 ~ 0.7 MPa (3 Way)

0.1 ~ 1 MPa (4 Way)

2.5 Product Specification

Model YT-720S YT-720D

Air Pressure Range 0 ~ 0.4 MPa 0 ~ 0.7 MPa 0.1 ~ 1 MPa

Flow Capacity(Cv) 0.2 0.084 0.75

Rating Current

AC 110V 130 mA (12 W)

AC 220V 60 mA (11 W)

DC 24V 580 mA (14 W)

Frequency 50 ~ 60 Hz

Explosion Proof Ex d IIC T6 (KCs)

Air Connection Rc 1/4 or 1/4 NPT

Conduit Entry G 1/2

Coil Insulation Grade Class F

Ambient Temperature

Operating -20 ~ 70°C (-4 ~ 158°F)

Explosion Proof -20 ~ 50°C (-4 ~ 122°F)

Housing Material Aluminum

Weight 0.86kg (1.9 lb) 1.3kg (2.8 lb)

Tested under ambient temperature of 20°C, absolute pressure of 760mmHg, and humidity of 65%.

Please contact Rotork YTC Limited for detailed testing specification.


Ver. 1.12 7

2.6 Certifications

※ All certifications below are posted on Rotork YTC Limited homepage(www.ytc.co.kr).

➢ KCs (Korea)

Type : Explosion proof construction for internal pressure

Rating : Ex d IIC T6

Certification No. : 15-KB2BO-0133

Ambient temperature : -20 ~ +50°C

➢ Electromagnetic Compatibility (EMC)

- EMC directive 2014/30/EC from April 2016

- EC Directive for CE conformity marking

2.7 Parts and Assembly

Fig. 2-1: YT-720S exploded view

http://www.ytc.co.kr/


Ver. 1.12 8

Fig. 2-2: YT-720D exploded view


Ver. 1.12 9

2.8 Product Dimension

Fig. 2-3: YT-720S

Fig. 2-4: YT-720D


Ver. 1.12 10

3 Operating Logic

3.1 YT-720S

As signal pressure is being supplied, the ⑥plunger rises and creates a secondary gap between the

⑨nozzle and ⑥plunger which results in primary air pressure exhaustion. When signal pressure has

been turned off, the ⑥plunger moves downward and blocks the channel. At the same time, the air

pressure will exhaust through the channel between the ⑥plunger, ②vent, and ①body cap.

Fig. 3-1: YT-720S Section


Ver. 1.12 11

3.2 YT-720D

When the signal voltage is given, the ⑥plunger rises up due to the electromagnetic force generated

by the voltage, so that the lower part of the ⑨nozzle and the ⑥plunger are opened and the passage

to the upper part of the spool in the valve opens. The spool is pushed down and the primary supply

pressure is output to the C2 port. When the signal voltage is again interrupted, the plunger falls down

and the nozzle is closed, and the air pressure in the upper part of the spool is released to the

atmosphere through the ⑥plunger internal flow path. The spool is raised by the gap difference and

primary supply pressure is output to the C1 port.

그림 3-2: YT-720D Section


Ver. 1.12 12

4 Installation

4.1 Safety and Installation Tips

When installing the unit, please ensure to read and follow safety instructions.

➢ Follow other explosion proof procedures and safety precautions.

➢ In case of hazardous area, please ensure there is no explosion gas in the atmosphere.

➢ Any input or supply pressures to valve, actuator, and / or to other related devices must be turned

off.

➢ Use bypass valve or other supportive equipment to avoid entire system “shut down”.

4.2 Tools for installation

➢ Hex key set for hex socket cap bolts

➢ (+) & (-) Screw drivers

➢ Spanners for hexagonal-head bolts

4.3 Manual Switch

The valve can be operated without the electric signal by using the manual switch. The manual switch

can be adjusted with tools such as flat screwdrivers. When the product is shipped from the factory,

the manual switch is set to the automatic position (A), meaning the position where the valve is

opened or closed by a normal electrical signal.

➢ YT-720S: When the manual switch is switched to the manual position (M), the valve is forcibly

opened without electrical signal. (IN → OUT)

➢ YT-720D: When the manual switch is in the automatic position (A), if an electric signal is input,

pneumatic pressure flows from IN → C2, and if the electric signal is blocked, pneumatic

pressure flows from IN → C1. But when the manual switch is switched to the manual position

(M), air pressure flows through IN → C2 without electrical signal.

※ Be sure to switch to automatic position (A) during normal operation.

※ Be careful not to overturn the manual switch with excessive force as it could damage the switch.


Ver. 1.12 13

Fig. 4-1: Auto Manual Switch

Fig. 4-2: 720D Flow direction according to position of auto manual switch without electric signal.


Ver. 1.12 14

5 Connection – Power

5.1 Safety

When installing a unit, please ensure to read and follow safety instructions.

➢ When installing in hazardous and explosive gas area, conduit tube or pressure-proof packing

union must be used. The compound charging box should be the flameproof type and must be

sealed completely.

➢ There is a conduit entry on the product. Conduit entry connection tap is G 1/2.

➢ Before connecting terminal, ensure that the power is off completely. Do not open the cover

when the power is still alive.

➢ Please use ring terminal to protect against vibration or any other external impact.

➢ The product should be grounded at outside or inside terminals of the product.

➢ Please use twisted cable with conductor section are 1.25mm2 and that is suitable for 600V

(complying with the conductor table of NEC Article 310). The outer diameter of the cable should

be between 6.35 ~ 10mm. Use shield wire to protect against electro-magnetic field and noise.

➢ Please do not install the cable near high noise equipment, such as high-capacity transformer or

motor. Please use shielded cable if necessary.

Fig. 5-1: Pressure-proof packing union Fig. 5-2: Flame proof type compound charge box


Ver. 1.12 15

5.2 Coil body and Rotator

The coil part rotates 360 degrees and the rotator, which is the conduit entrance, can be turned in a

range of 265 ° to a convenient position for operation.

Fig. 5-3: Rotation of YT-720S Coil body

Fig. 5-4: Rotation of YT-720D Coil body

Fig. 5-5: Rotation of Rotator


Ver. 1.12 16

5.3 Connection of terminal

1. Loosen the Rotator Lock Bolt and rotate the Rotator to the desired position

2. Open the Rotator Cover, connect the ground using the grounding bolt (E indicator), and connect

the power terminal in the same way. At this time, the polarity of the terminal can be connected

without distinguishing + and – for both AC or DC.

※ Be sure to connect to the ring terminal supplied from the terminal.

3. Close the Rotator Cover and tighten the Rotator Lock Bolt.

Fig. 5-6: Connecting terminals


Ver. 1.12 17

6 Connection - Air

6.1 Safety

➢ Supply pressure should be clean and dry air – avoiding moisture, oil and dust.

➢ Always recommended to use air filter regulator (i.e. YT-200 series).

➢ Do not disassemble the product without prior consultation with manufacturer. If disassembling is

inevitable, please contact Young Tech Co.,Ltd or your dealer.

➢ Rotork YTC Limited has not tested positioner’s operation with any other gases other than

clean air. Please contact Rotork YTC Limited for any questions.

6.2 Supply Pressure Condition

➢ Dry air with dew point of at least 10℃ lower than ambient temperature.

➢ Avoid from dusty air. If require, we recommend to use air filter regulator which contains 5 micron

or lower filter (YT-200)

➢ Avoid oil.

➢ Comply with ISO 8573-1 or ISA 7.0.01.

➢ Use within the range of pneumatic pressure specified in the product specification.

➢ When solenoid valve is used on an actuator, set the pressure output from the regulator to 10%

higher than the operating pressure of the actuator or the spring range pressure of the actuator

6.3 Piping Condition

➢ Ensure inside of pipe is clean of obstructions.

➢ Do not use pipeline that is squeezed or shows any type of damamges.


Ver. 1.12 18

6.4 Connecting piping of YT-720S

Fig. 6-1: Installation example by piping and without mounting bracket

Fig. 6-2: Installation example


Ver. 1.12 19

6.5 Connecting piping of YT-720D

➢ If the exhaust ports E1, E2 are completely blocked, the product will not operate.

➢ If you do not use it as a double-action type, you can use it as a single-action type by blocking the

unnecessary ports of the output ports C1 or C2. At this time, exhaust ports E1 and E2 should all

be open.

Fig. 6-3: Installation example by piping and without mounting bracket

Fig. 6-4: Example of YT-720D on an actuator

Fig. 6-5: Installation example


Ver. 1.12 20

7 Maintenance

There are coil assembly and valve that can be replaced during maintenance in the solenoid valve.

Solenoid valve’s valve and coil assembly can be easily disassembled from the field. However, if this

has affection on explosion proof performance, do not disassemble the coil assembly or valve, and

then replace the YT-720 itself or remove the product from the site and ask for repair from the supplier

or the manufacturer. Please observe the safety instructions of the site and the safety instructions of

this manual to avoid any damages to the product and injuries during maintenance.

Fig. 7-1: YT-720S Fig. 7-2: YT-720D


Ver. 1.12 21

8 Troubleshooting and repair

1) No response from the plunger after input signal has been supplied.

➢ Please check that the signal voltage matches the rated voltage of the product. If the signal

voltage differs from the rated voltage, match the signal voltage to the rated voltage.

➢ Please check the resistance between (+) and (-) poles. If the resistance is too high, the coil must

have been burnt.

2) Plunger operates but no output air when input signal has been supplied.

➢ Please check if supply pressure from the regulator is stable.

※ Following is only for YT-720D

➢ Check that the supply pressure from the regulator is less than 0.12 MPa. If the supply pressure

is too low, the spool inside the valve will not operate.

➢ Check that the exhaust port is not blocked. In both cases of single acting and double acting

actuators, the exhaust port should not be blocked.

➢ Check that the output port to be used is not blocked.

➢ Check that the spool in the valve body is fixed. If there is no problem, it is highly likely that the

spool is fixed when there is no output of the supply pressure even if the manual switch is

manually operated and the plunger is forcibly moved.

3) Air pressure outputs from C1 when there is no input signal.

➢ Please check if switch is at automatic (A) position.

➢ Check that the supply pressure from the regulator is less than 0.12 MPa. If the supply

pressure is too low, the spool inside the valve will not operate.


Ver. 1.12 22

Manufacturer: Rotork YTC Limited

Address: 81, Hwanggeum-ro, 89 Beon-gil, Yangchon-eup, Gimpo-si, Gyeonggi-do, South Korea

Postal code: 10048

Tel: +82-31-986-8545

Fax: +82-70-4170-4927

Email: [email protected]

Homepage : http://www.ytc.co.kr

Issued : 2020-08-10

Copyright © Rotork YTC Limited. All Rights Reserved.

mailto:[email protected]

http://www.ytc.co.kr/

Documents

Solenoid Valve PRODUCT MANUAL YT-720 SERIES · Solenoid Valve PRODUCT MANUAL YT-720 SERIES YT-720S YT-720D Rotork YTC Limited VERSION 1.11 . Solenoid Valve YT-720 Series Product Manual