Rotex 51424 Service manual

IM No. : IM/V/0021, Rev. 2
Date: 06.11.2017
Page 1 of 6
MOUNTING, OPERATING, TESTING & MAINTENANCE INSTRUCTIONS
FOR ROTEX 5/2, 3/2 CONVERTIBLE NAMUR SOLENOID VALVE
MODEL 51424, 51424LW, 51424IS
ROTEX retains all rights to this publication.
All details within this manual and the catalogue are subject to change without manner.
ROTEX will not be responsible for any damage whatsoever arising from the use of the Solenoid Valve, due to misuse or
incorrect installation or misinterpretation of the information contained herein.
SPECIFICATION OF STANDARD SOLENOID VALVE
CONNECTION
VALVE TYPE
Inlet
Outlet
Exhaust
Outlet
Exhaust
Pilot Vent
External
Pilot Inlet
51424
1
2 (NAMUR)
3
4 (NAMUR)
5
6
-
A) OPERATING PRINCIPLE
On de-energized condition of the solenoid, pressure applied at the inlet port, a part of media from the inlet port # 1 is drawn
through the internal pilot passage which is blocked under Plunger. In case of External Pilot Operated Valve the external
pilot port # 7 is drawn through the external pilot passage is blocked by plunger. In this state the Inlet port # 1 & Outlet port
# 4 is connected. Outlet port # 2 & Exhaust port # 3 are connected; Exhaust Port # 5 is blocked.
On energized condition of the solenoid, Plunger moves up and media from pilot passage acts on the piston assembly thus,
poppet assembly goes down and connecting. In this state Inlet port # 1 & Outlet port # 2 is connected. Outlet Port # 4 &
Exhaust port # 5 are connected; Exhaust port # 3 is blocked.
NOTE: IN CASE WHEN THE VALVE IS OPERATED AS EXTERNAL PILOT OPERATED VALVE, THE PILOT AIR
PRESSURE SHOULD BE MINIMUM 2 bar OR > MAIN FLUID PRESSURE WHICHEVER IS HIGHER.

IM No. : IM/V/0021, Rev. 2
Date: 06.11.2017
Page 2 of 6
IDENTIFICATION ON THE SOLENOID VALVE
a) VALVE MARKING
Label on the ROTEX Solenoid Valve shows the following details:
(1)
Logo + Name & address of the Manufacturer
(2)
Valve Type / Code
51424
=
Valve Model
Suffix
=
Nil
6
=
Orifice 
2R
=
Port Connection
B5
=
Body Material
M8
=
Manual Override
S2
=
Seal Material
(3)
Work Order reference / Sr. No. of the Valve
(4)
Operating Pressure
(5)
Month & Year of manufacture
(6)
Valve Symbol
(7)
Media
(1)
ROTEX AUTOMATION LIMITED
VADODARA-390010, INDIA
FLUID CONTROL SYSTEM
CODE : 51424-6-2R-B5-M8-S2
ATM
2-10
MEDIA
AIR
DATE
9/2016
Wo. No.
16100650/10
(6) (2) (4) (3) (5) (7)
b) SOLENOID MARKING
(1)
ROTEX
VADODARA –390010,
INDIA
(1)
(2)
Logo + Name of the Manufacturer
Solenoid Type
III
110V
=
=
Solenoid Size III
Solenoid Voltage
III-110V-DC-25-H
DC
=
Solenoid Current
16100650-09/16
25
=
Solenoid Construction
H
=
Solenoid Class H Insulation
(3)
Work order No. Manufacturing Month / Year
(2) (3)
(B) MOUNTING/INSTALLATION PROCEDURE:
1. ENSURE THAT:
a) While storing, keep the valve in cool, dry, dust free area.
b) On receipt of the valve, in case if the same is to be removed from the sealed plastic bag for
inspection/testing, put them back with dust plugs on its ports and sealing the plastic bag as soon as the
inspection/testing is over.
c) The valve should be removed from its card board and/or plastic bag just before the installation.
d) Flush lines before installing the valve.
e) To avoid pressure drop and to achieve optimum parameters, Pipe / Tube / Fitting from the source of
pressure to the valve and to the connected equipment should have ID which is NW (Orifice) of the
valve.
f) To avoid pressure drop, if more than one valve is being operated simultaneously from a common
header, then minimum ID of the header can be calculated as under.
ID Header = (NW2n)
n = Number of Valves operating at a time and which are connected to a common header,
NW = Orifice of the Valve.
g) Incorporate filter in the line to avoid hard particles entering into the valve.
h) Do not try to drill any additional holes or machine, modify any of the valve components.
i) Inlet pressure does not exceed rated pressure.
j) Hemp-Filaments, ’Jute’ or even Teflon-Ribbons are normally not required, as the port connections of
ROTEX Valve is accurately machined.
k) Do not cover first two thread pitches with Teflon tape or sealant. To avoid over lap of the Teflon ribbon or
cuts generated while tightening, getting carried away into the valve.

IM No. : IM/V/0021, Rev. 2
Date: 06.11.2017
Page 3 of 6
l) For Solenoid Valve to be installed in European Union, check the applicability for ATEX, PED
Directives. Refers separate Instruction Manual for ATEX approved Solenoid Valve.
2. Provide Dust Cap on the exhaust port or ensure that the valve is mounted such a way that dust particles / rain
water / process fluid do not enter into the valve through exhaust port of the valve. You can connect bend pipe of
ID > NW of the valve so that the exhaust port is not directly (straight) open into the atmosphere.
3. The process fluid etc. do not fall on the valve body.
4. Install valve in such a way that the rain water / other process fluid dripping along the cable does not fall on the
SOV and has no possibility to run along the cable and enter into the Terminal area.
5. In case if the valve is installed in potentially Hazardous area, check for the temperature class of the Solenoid to
avoid explosion due to heated Solenoid / other components.
6. Provide fuse of proper rating to avoid excess current passing through the Solenoid and thereby avoiding over
heating.
7. It is not likely however; the user is advised to protect the valve against lightening as the same is not assessed.
8. Check internal components (wetted) parts for its compatibility with fluid passing through the valve.
9It is recommended to replace all the Rubber Parts including Plunger Assembly (Repair Kit) in case if the
valve is to be installed and put in service after 2 years from the date of manufacture.
10. Install valve matching Port A of the Actuator (active port) to the Port 2 of the Solenoid Valve.
11. Fix M5 Grub Screw in one of the M5 free hole of the Actuator. This is to avoid turning at the valve during
maintenance (Refer Photo-XX).
12. Procedure to convert 5/2 to 3/2.
a) Remove Valve.
b) Check disk position at Port-4 of the solenoid valve.
c) To convert valve from 5/2 to 3/2, remove disk at Port-4 and refix the same after turning 180º.
(Refer Photo-XX).
13. 51424 can be operated with 6 Watt / 8 Watt Solenoid.
14. 51424LW can be operated with 2 Watt Solenoid.
15. 51424IS can be operated with Low Power Intrinsically Safe Solenoid.
16. Use SP2 Spacer Plate with long bolts in case when the solenoid interferes with Actuator body.
ELECTRICAL
1. Verify name plate affixed on the Solenoid.
2. Connect the power supply according to the voltage rating of the Solenoid
3. Ensure that the cover of Junction Box/Terminal Box is properly tightened wherever applicable.
4. Install valve in such a way that the rain water / other process fluid dripping along the cable does not fall on the
SOV and has no possibility to run along the cable and enter into the Terminal area.
5. Fill in the space between cable and gland entry with a proper sealant. If necessary, you may mount the valve
upside down or in any other direction.
6. Ensure that the Solenoid enclosure meets process and local authority requirement.
7. The Plug In, Terminal Box, FPJB, IS Solenoids are provided with test leads. Remove them before final
installation.
8. Check for proper connections for the Solenoid which are polarity sensitive e.g. (a) Latched Solenoid (b) Ex ia
Solenoid.
9. Refer separate manual for construction of the Solenoid and for specific instructions related to Solenoid
e.g. (a) Ex ia (b) Latched Solenoid (c) Exd Solenoid IP 67
10. Ensure that the solenoid construction is selected properly meeting the environment in which the valve is
supposed to be installed e.g. use of Exd or Ex ia solenoid for valve to be installed in hazardous location or
Weatherproof Solenoid having IP 67 for outdoor installation.
11. Flying Lead Solenoid is not recommended to be used for outdoor or indoor application where water/liquid
splashing or high humidity is present.
MANUAL OVERRIDE OPERATION
(A) PUSH & TURN TYPE (M6)
In normal condition of manual override, when we applied the pressure, a part of media from the inlet port # 1 is
drawn through the internal pilot passage which is blocked under Plunger. In case of External Pilot Operated Valve
the external pilot port # 7 is drawn through the external pilot passage is blocked by plunger. In this state the Inlet
port # 1 & Outlet port # 4 is connected. Outlet port # 2 & Exhaust port # 3 are connected; Exhaust Port # 5 is
blocked.
To operate the manual over ride push and turn clock wise, thus plunger moves up and media from pilot passage
acts on the piston assembly thus, poppet assembly goes down and connecting. In this state Inlet port # 1 & Outlet
port # 2 is connected. Outlet Port # 4 & Exhaust port # 5 are connected; Exhaust port # 3 is blocked. To release
the valve, turn anticlockwise.
(B) PUSH TYPE (M8)

IM No. : IM/V/0021, Rev. 2
Date: 06.11.2017
Page 4 of 6
In normal condition of manual override, when we applied the pressure, a part of media from the inlet port # 1 is
drawn through the internal pilot passage which is blocked under Plunger. In case of External Pilot Operated Valve
the external pilot port # 7 is drawn through the external pilot passage is blocked by plunger. In this state the Inlet
port # 1 & Outlet port # 4 is connected. Outlet port # 2 & Exhaust port # 3 are connected; Exhaust Port # 5 is
blocked.
To operate the manual override push it, thus plunger moves up and media from pilot passage acts on the piston
assembly thus, poppet assembly goes down and connecting. In this state Inlet port # 1 & Outlet port # 2 are
connected. Outlet Port # 4 & Exhaust port # 5 are connected; Exhaust port # 3 is blocked. To release the valve,
turn anticlockwise. Bring the valve in original position release the manual override.
TESTING OF THE VALVE AT THE TEST BENCH
Check at least once in 3 years or following your routine maintenance schedule.
a) Apply rated pressure at inlet port of the valve.
b) Plug outlet ports.
c) Check operation of the valve and leakage at the exhaust ports and pilot vent at the rated and minimum working
pressure by applying 75% to 120% rated voltage.
d) While keeping the solenoid de-energized, check operation and leakage from exhaust and pilot vent ports of the
valve at the rated and minimum working pressure by operating Manual Override.
Check at least once in 3 years or following your routine maintenance schedule.
a) Apply rated pressure at inlet port of the valve.
b) Plug outlet ports.
c) Check operation of the valve and leakage at the exhaust ports and pilot vent at the rated and minimum working
pressure by applying 75% to 120% rated voltage.
e) While keeping the solenoid de-energized, check operation and leakage from exhaust and pilot vent ports of the
valve at the rated and minimum working pressure by operating Manual Override.
f) Without connecting air supply to the valve, operate Manual Override. Energize and De-energized Solenoid to
check for the plunger movement (normally movement should not be there) which can be checked by click sound.
After operating Manual Override if plunger movement is found, reduce length of the manual override by 0.3mm
from its tapper end. Continue this till click sound stops.
g) Check the insulation resistance of the Solenoid by applying 500V DC at terminals and the solenoid housing. It
should be more than 100 Mega Ohms.
RECOMMENDED SPARES
a) Seal Kit (O Ring).
b) Plunger assembly.
c) Spare Solenoid.
d) Repair Kit
RECOMMENDED MAINTENANCE PREVENTIVE
Replacement of Complete Set of O Ring ……Once in 5 years or 2 million operations.
- Solenoid O Ring, Guide O Ring,
- MA O Ring, Body O Ring,
- Seat O Ring, Kolben O Ring, Boden O Ring
Replacement of Plunger Assembly ………Once in 5 years or 2 million operations
Replacement of the Solenoid ………As and when required.
Check of Insulation Resistance, Resistance of the Solenoid…Once in a year (should be > 100 MOhms @
500V DC.
Check Resistance of the Solenoid………Replace Solenoid if the resistance reduces more
than 5% computed at 20ºC as compared to its
Initial value.
MAINTENANCE –GENERAL INSTRUCTION
The Solenoid Valve must be removed from the site and has to be maintained under safe conditions.
All air and electrical connections must be switched off before removing valve from the line.
It is recommended to replace complete set of O Ring even if one of the O Ring is damaged. This is to ensure
trouble free operation of the valve and will avoid its premature failure.
Using Grease other than Silicon base Molykote M55 will lead to premature failure of O Rings of the ROTEX
Solenoid valve.
If necessary to clean the components, do not use Kerosene, Diesel, Petrol to clean valve as this damages
the O Rings and other rubber material. Instead use light Detergent Soap Solution.
Ensure that the components are free from dust, dirt, lint and metal burrs.
Twisting of O Ring should be avoided. Ensure that the twist is removed before fitting matching part.

IM No. : IM/V/0021, Rev. 2
Date: 06.11.2017
Page 5 of 6
While closing the matching part, the matching part should be pushed in a straight line. Turning motion should be
avoided.
Pinching of O Ring at the groove corner at the time of closing gland should be avoided.
User is requested to use safe practice for maintenance.
It is important to place the dismantled Valve Parts on a clean paper or cloth in same sequence in which you have
dismantled them.
Ensure to keep all the components of the valve separately to avoid their mixing up. The component appears tobe
same may have small differences which will cause malfunction if interchanged.
In case of difficulty you should contact the Agent, Distributor or ROTEX directly.
Using ROTEX genuine spares will guarantee you trouble free operation and will avoid premature failure.
(A) TO REPLACE SOLENOID
1) Open dome nut and pull out solenoid
2) Replace new solenoid ensuring the construction, voltage and current meets the requirements.
3) Tighten the dome nut applying torque of 0.2 kgm to 0.35 kgm to avoid over tightening of the solenoid.
4) Measure and record resistance of the Solenoid.
(B) TO REPLACE GUIDE ASSEMBLY (CORE TUBE)/ PLUNGER
1) Open dome nut and pull out solenoid.
2) Open Guide Assembly (Core Tube) using guide opening tool (depending on the Guide Assembly (Core
Tube) fitted on the valve.
3) Remove Plunger Assembly.
4) Replace the necessary defective parts ensuring that the plunger assembly spring and the retaining ring.
5) The Plunger is interchangeable and can be fitted in the existing Guide Assembly (Core Tube).
6) Fix Guide Assembly (Core Tube) using correct tool.
7) Fix the solenoid and dome nut as per Point-3 of procedure A.
8) Even though it is not recommended, in case if required, the Guide Assembly (Core Tube) can be opened
using plier or other similar tool ensuring that the same does not damage anything or component and the
plier is tighten above weld joint (weld joint should be at the centre of plier jaw width).
(C) REPLACEMENT OF MANUAL OVERRIDE
1) Remove Grub Hex Socket Set Screw and pull out Manual Override.
2) Replace new Manual Override applying light layer of Silicon Grease Molykot M55 and tighten the grub
screw fully till the Manual Override stops traveling in and out.
3) Open the Grub Hex Socket Set Screw slightly (1/4 turn) and check the smooth movement of the grub
screw.
4) Without connecting air supply to the valve, operate Manual Override. Energize and De-energize
Solenoid to check for the plunger movement (normally movement should not be there) which can be
checked by click sound. After operating Manual Override if plunger movement is found, reduce length of
the manual override by 0.3mm from its taper end. Continue this till click sound stops.
(D) REPLACEMENT OF O RINGS
1) Remove solenoid if necessary as per Procedure “A”.
2) Remover Deckel (Cover) by opening four screws.
3) Remove bottom plate by opening CSK Allen Head screws.
4) Remove Ventilboden (Valve Bottom).
5) Remove Ventilfeder (Valve Spring). Ensure that the location of the same are not interchanged.
6) Open piston assembly using special tool at Kolben and opening Nut.
7) Pull out Ventilteller (Pressure Plate) and Kolben Assembly.
8) Pull out Hulse and remove all O Rings [Piston O Ring, Seat O Ring, etc…].
9) Clean components.
10) Fix new O Rings applying light layer of Molykot M55 grease.
11) Ensure that the O Rings and other rubber parts are compatible to the media passing through the valve.
12) Replace MA O Ring, Body Pilot O ring and Guide O ring following procedure “B”.
13) Reassemble the valve.
14) Check operation and leakage of the valve.
15) Contact ROTEX in case of any difficulty.
STORING,CLEANING AND MOUNTING OF ELASTOMERS : SYNTHETIC RUBBER PRODUCTS
Store Plunger, O Ring Set in sealed polyethylene bag, kept in cool, dry, dust free area and avoid direct contact
with all light sources emitting ultra violet rays, or contact with fumes, solvents, fuels, lubricants, chemicals, acids,
disinfectants.
Follow Maintenance General Instruction & specific procedures to replace O Ring set as listed above.

IM No. : IM/V/0021, Rev. 2
Date: 06.11.2017
Page 6 of 6
3/2 Disk Position
Photo –1
5/2 Disk Position
Photo –2
Manual Override “ON”
Photo –3
Manual Override “OFF”
Photo –4
Flat Face this side
Photo –5
Plunger with fixed conical &
cylindrical seal
Photo –6
Plunger with moving seal
(New Design Plunger)
Photo –7
Locating spot for Grub
Screw
Photo –8
Contact:
ROTEX AUTOMATION LIMITED
987/11, GIDC, MAKARPURA, VADODARA –390010, INDIA
Tel. : [phone] Fax : [phone]
E-mail : [email protected] Website : www.rotexautomation.com