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Serpar Double Valves with E-p Monitor

1. Repair Symptoms Possible Causes Procedures No lockout Inadequate air supply A Inadequate voltage at solenoids B Both pilot solenoids inoperative Cc Faulty sealing on monitor spool J K Contaminants in monitor L Faulty lockout switch M Have both lockout and Main inlet poppets not sealing E small exhaust air flow Pilot poppet not sealing D Faulty pilot solenoid c Have lockout but Proceed to TEST 2 no exhaust air Will not reset Faulty reset solenoid l Incorrect voltage at reset solenoid H Faulty lockout switch M Contaminants in monitor L Resets correctly Proceed to TEST 3 Locks out intermittently Inadequate air supply A Incorrect voltage at pilot solenoids B Varnish deposits in valve F Excessive lubrication N Excessive vibration o Valve performs normally Transient foreign material P Dirty or undersized silencer Q Locks out on first cycle Proceed to TEST 4 Locks out as overrides Inadequate air supply A are depressed Jammed pilot solenoid plunger Cc Pilot poppet not sealing D Varnish deposits in valve F Excessive lubrication N Leaking piston poppet seal G Locks out as overrides Varnish deposits in valve F are released Main inlet poppet not sealing E Excessive lubrication N Operation normal Faulty solenoid or loose pilot cover Cc with overrides www rosscontrols com 5 REPAIR PROCEDURES INADEQUATE AIR SUPPLY Even though the air supply pressure is in the correct 30 to 125 psig 2 to 8 5 bar
2. 5b Single Input Wiring Diagram with Pilot Solenoid Diagram with Pilot Solenoid Circuit Open Circuit Open 2 2012 ROSS CONTROLS All Rights Reserved E P MONITOR LOCKOUT AND RESET Therefore if one of the main valve elements opens before the other due to a malfunction within the valve or some other element in the system which affects the valve function inlet pressure via passage 6 will be applied to one end of the spool sooner than at the other end When the pressure differential exceeds 2 bar 30 psi the pressure imbalance causes the spool to shift tripping switch actuator pin K This shifts switch L and breaks the circuit to the pilot solenoids see Figure 5a and 5b below With the pilot solenoids de energized the pilot valves close and air pressure on the pistons of the main valve elements is exhausted The main valve elements then return to their de actuated positions and air pressure on the ends of the E P spool is exhausted When switch L is shifted the valve is said to be locked out and operation cannot be resumed until the E P monitor is reset Note also Figure 5a and 5b that terminals 3 and 7 have been connected This allows a panel light bell or other electrical device to be wired through terminals 3 and 7 to serve as a lockout indicator RESETTING THE E P MONITOR Caution To avoid the potential for injury and to ensure that the equipment controlled by the valve does not begin operating immediatel
3. 7677 for assistance TROUBLESHOOTING CHART If the valve fails to operate properly apply the Tests given in the chart below Check for Symptoms Possible Causes and Repair Procedures are given for each symptom The repair procedures are detailed on the following pages After the valve is repaired follow the Test Procedure on page 4 before returning the valve to service Tests TEST 1 Electrical power to solenoids must be off Remove silencer Check for lockout and for exhaust air NOTE With just one valve element in the actuated position a small air flow past one of the spool elements is normal and should not be confused with full exhaust air flow TEST 2 With electrical power still off and silencer removed attempt to reset monitor Check for lockout TEST 3 Take normal press operation safety precautions during this test to ensure that there is no danger to personnel or equipment when the press cycles With silencer removed and monitor reset cycle valve several times by energizing the solenoids in the normal manner TEST 4 With electrical power off silencer and monitor reset proceed as follows Take normal press operation safety precautions to ensure that there is no danger to personnel or equipment when the press cycles Actuate the valve by depressing holding then releasing both manual overrides Be sure to depress overrides simultaneously ROSS
4. E to return to their normally closed positions Pilot pressure on the main valve pistons J is exhausted through exhaust port 3 via internal exhaust passages not shown The main valve piston poppets J and inlet poppets U and V return to their normal de actuated positions Inlet air is again blocked from outlet port 2 by poppets U and V Pressure at outlet port 2 at the ends of spool W and in the monitoring passages 6 is exhausted through exhaust port 3 This completes the normal operating cycle and the valve has returned to the Conditions at Start described above A Figure 2 Solenoids Energized E P MONITOR LOCKOUT AND RESET SOL INPUT COMM RESET SOL RESET SOL E P MONITORING and LOCKOUT k E The heart of the E P monitor is its spool K m HMdelslsisiel7 isis W and associated switch L see Figure m W aT L 3 The spool is kept in its normal position NI d OM by centering springs M Switch L is a Paa two position momentary latching switch ir gt aa wired as shown in Figure 4a and 4b In its i iia ii aii 6 normal position it completes the electrical circuit to the pilot solenoids through Q Fi i Dustin i igure 4a Dual Inpu i Si terminals 3 and 4 Figure 3 Horizontal Cross Wiring Diagram with Pilot ag bb Section of E P Monitor Solen
5. PA 3 Remove the spool and spring assembly Inspect the seals for damage and replace if necessary Inspect the spool bore for burrs or grit that might have damaged the seals Lubricate the bore lightly and reassemble the monitor WORN SPOOL BORE A worn spool bore in the E P monitor can affect sealing which can result in nuisance lockouts or the monitor not to lockout This can create the potential for personal injury or damage to equipment To check the bore disassemble the monitor as described in Repair Procedure J If bore is worn entire E P monitor must be replaced CONTAMINANTS IN SPOOL BORE A buildup of grease oil or water in the spool bore can restrict or prevent movement of the spool This can result in failure of the monitor to lock out or reset when it should and so can create the potential for injury or damage to equipment To inspect and clean s O Z a p i f J RA o Figure 12 Cross Section of E P Monitor ROSS the bore follow disassembly steps in Repair Procedure J LOCKOUT SWITCH NOT WORKING Before checking the lockout switch verify that the reset solenoid is functioning properly see Repair Procedures H and and that contaminants are not preventing movement of the monitor spool see Repair Procedure L To check switch operation proceed as follows 1 Turn off the electrical supply to the pilot solenoids and the
6. and produce a lockout Shock absorbing mounting for the valve can help to isolate it from such vibration TRANSIENT FOREIGN MATERIAL If the valve resumes normal operation after being reset the cause of the lockout may be a transient foreign particle A bit of scale or other foreign material could lodge at various points in the valve to cause a lockout After resetting the air flow of the next operating cycle can wash the foreign material out so that the valve continues to operate normally This situation is most common after a period of press inactivity An efficient and well maintained filter close to the valve can help to eliminate this problem UNDERSIZED or PLUGGED SILENCER Caution Restricting the exhaust port of a double valve can adversely affect its operation Silencers must be resistant to clogging and have a flow capacity greater than the exhaust capacity of the valve ROSS expressly disclaims all warranties and responsibility for any unsatisfactory performance or injuries caused by the use of the wrong type wrong size or inadequately maintained silencer installed with a ROSS product The silencer supplied with SERPAR double valves see Figure 13 is designed to create minimum back pressure However after long usage with contaminant laden air it may become clogged The increased back pressure can then cause erratic motion of the valve elements and lead to intermittent lockouts A dirty silencer should be removed and cl
7. be only a small flow of exhaust air Release the manual override Exhaust air flow should stop 4 Try to energize both pilot solenoids The procedure in step 3 should have caused the E P monitor to lock out so that it is not above the specified range causes excessive poppet impact and can shorten the life of the valve Temperature Range ROSS double valves have an operating media temperature range of 40 F to 175 F 4 C to 80 C and an ambient temperature range of 40 F to 120 F 4 C to 50 C Improper valve action and or a shortening of valve life can result if these temperature limits are not observed possible to energize the solenoids No pressure should appear at either the outlet or exhaust port Turn off the electrical supply to the pilot solenoids 5 Reset the monitor by briefly energizing the reset solenoid Simultaneously energize both pilot solenoids Inlet and outlet pressures should be equal There should be no leakage at the exhaust Cc port De energize both solenoids 1 6 Simultaneously energize both pilot solenoids then depress manual override P De energize both 3 solenoids while holding override P 13 depressed There should be only a small flow of exhaust air Release the manual override Exhaust airflow should stop 7 Try to energize both pilot solenoids The procedure in step 6 should have caused the E P monitor to lock out so that it is not possible to energize the solenoid No pressure should appea
8. range the air volume supplied can be too small An inadequate air volume causes excessive pressure drop during valve actuation i e pilot air supply is sufficient to unseat the main valve elements but the pressure drop which results from filling the outlet volume depletes the pilot air supply The main valve elements may be only partially actuated so that inlet air flows out the exhaust The lowered pilot pressure can also exaggerate the effects of small differences in the operating characteristics of pilots and valve elements so that the valve elements may not move simultaneously This can produce intermittent lockouts Check for very long undersized or pinched supply lines sharp bends and restrictive fittings All can reduce the air volume supplied to the valve Remember too that the air volume supplied can be insufficient if more pneumatic devices are connected to a circuit than the compressor is designed to serve INCORRECT VOLTAGE AT SOLENOIDS Solenoids are rated for continuous duty at 85 to 110 of the voltage shown on the pilot housing A supply voltage that does not fall within this range can cause nuisance lockouts premature solenoid burnout or impact damage To check the electrical supply first shut off exhaust and lockout the air supply to the valve Remove the junction box cover at the bottom of the valve Attach voltmeter leads to the supply terminals Read the voltmeter while the solenoids are energized If the voltage f
9. reset solenoid 2 Remove monitor cover 3 Disconnect any circuit that may be connected to terminal 7 but leave the wire from the lockout switch connected 4 Observe actuator pin K Figure 12 If itis extended use the tip of a screwdriver to push it into the retracted position 5 Attach ohmmeter leads to terminals 3 and 4 The meter should give a low reading Next attach the leads to terminals 3 and 7 The meter should give an infinite reading 6 Create a lockout by depressing just one of the manual overrides Switch actuator pin K should now be extended 7 Attach ohmmeter leads to terminals 3 and 4 The meter should give an infinite reading Next attach the leads to terminals 3 and 7 The meter should show a low reading 8 If the switch actuator does not fall securely into its extended and retracted positions or if the switch fails the electrical tests in steps 5 or 7 the switch is not functioning correctly and must be replaced N EXCESSIVE LUBRICATION Excess oil on the piston walls Y Figure 11 can sometimes cause erratic valve action and result in intermittent lockouts Although lubrication is not required for this valve if a lubricator is used it should deposit only a thin film of oil on the piston walls Remove excess oil and reassemble valve Check lubricator flow rate see page 4 EXCESSIVE VIBRATION Excessive vibration from heavy machinery can cause the lockout switch contacts to flutter or even shift
10. shifted air escaping past the spool in the valve stem of the closed valve element see Figure 6 must be quickly exhausted to keep outlet pressure at or below the design pressure of two per cent of inlet pressure Therefore use only a properly sized and designed silencer Electrical Conduit Port 13 Itis very important that the electrical supply be of the correct voltage and frequency Solenoids are rated for continuous duty at 85 to 110 of the voltage shown on the pilot housing A supply voltage that does not fall within this range can cause nuisance lockouts or premature solenoid burnout If electrical power is supplied by a transformer it must be capable of handling the inrush current of the solenoids without significant voltage drop When installing the valve the hot wire for the pilot solenoid supply is connected to terminal 3 and the ground wire to terminal 1 Supply lines for the reset solenoid are connected to terminals 8 and 9 See Figure 4 for wiring diagram www rosscontrols com 3 INSTALLATION NOTES Mounting Position It is recommended that double valves be mounted with the pilot assembly upward Pressure Range ROSS double valves have an operating pressure range of 30 to 125 psig 2 to 8 5 bar Pressure below this range can create the potential for injury by reducing the speed with which the outlet volume is pressurized or by rendering the monitor inoperative It can also cause intermittent lockouts Pressure
11. the wires brought in by the electrical conduit and the conduit itself Also extra care is required when removing the E P monitor or adaptor plate because there are parts such as springs and O rings which can separate from the valve body Care is also required in withdrawing the solenoid leads from the passage through the valve body To remove the valve elements first remove the retaining rings H Figure11 end plugs W and springs BA at the lower ends of the bores Pull inlet poppets U and V off the valve stems and remove the remaining parts of the valve elements through the top of the valve body If the inlet poppets U and V are damaged or have deteriorated replace them Deteriorated poppet material suggests the use of incompatible lubricants Only lubricants such as those described on page 4 should be used BB BB While the valve is disas sembled also inspect the y piston poppets J for damage or deterioration Inspect the bores for varnish deposits vi or excess wear See Repair BA Procedures F and G Lightly w lubricate moving parts and H reassemble the valve VARNISH DEPOSITS Varnish deposits in the valve may affect the movement of a piston and cause intermittent lockouts Varnish results from the action of oxygen on lubricating oils and can be aggravated by excess heat Varnish can also come from overheated compressor oil carried over into the airlines and deposited in the valve 5 _ U Figure 10 Cros
12. 03 inch If a stem does not move i T cc smoothly the insert should be replaced Inspect the poppets E and their seats for foreign particles or damage Carefully clean out foreign material If the poppets are swollen or have deteriorated improper lubricants may be the cause See page 4 for information about compatible lubricants If a poppet or inlet upper seat is worn or damaged the insert must be replaced Blow out passages 5 and 9 to remove loose dirt particles If an exhaust lower seat is worn or damaged the entire pilot must be replaced MAIN INLET POPPET NOT SEALING If one of the inlet poppets is not sealing air can be detected escaping at the exhaust port Foreign particles are sometimes responsible for holding a poppet off its seat Manually cycle the valve several times to see if the flow of air through the valve will flush out the particles Take normal press operation safety precautions during this procedure in order to avoid injury or damage to equipment If cycling the valve does not clear the valve it will be necessary to disassemble and clean the valve To disassemble the valve first turn off the electrical power to the valve Shut off exhaust and lock out the air supply Remove the pilot assembly E P monitor and adaptor plate if used Disassembly Note Before removing the pilot assembly the solenoid leads must be slipped off the solenoid terminals When removing the monitor it may also be necessary to disconnect
13. 24 9040 Fax 91 44 2625 8730 Email rossindia airtelmail in Your local ROSS distributor is DIMAFLUID s a s Saint Ouen France Telephone 33 01 4945 6565 Fax 33 01 4945 6530 Email dimafluid dimafluid com www dimafluid com Warranty All products sold by ROSS CONTROLS are warranted for a one year period with the exception of all Filters Regulators and Lubricators FRLs which are warranted for a period of seven years from the date of purchase to be free of defects in material and workmanship ROSS obligation under this warranty is limited to repair or replacement of the product or refund of the purchase price paid solely at the discretion of ROSS and provided such product is returned to ROSS freight prepaid and upon examination by ROSS is found to be defective This warranty becomes void in the event that product has been subject to misuse misapplication improper maintenance modification or tampering THE WARRANTY EXPRESSED ABOVE IS IN LIEU OF AND EXCLUSIVE OF ALL OTHER WARRANTIES AND ROSS EXPRESSLY DISCLAIMS ALL OTHER WARRANTIES EITHER EXPRESSED OR IMPLIED WITH RESPECT TO MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ROSS MAKES NO WARRANTY WITH RESPECT TO ITS PRODUCTS MEETING THE PROVISIONS OF ANY GOVERNMENTAL OCCUPATIONAL SAFETY AND OR HEALTH LAWS OR REGULATIONS IN NO EVENT IS ROSS LIABLE TO PURCHASER USER THEIR EMPLOYEES OR OTHERS FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES WHICH MAY RESULT FROM A BREACH OF
14. Figure 6 Faulted Mode with One Figure 7 E P Spool Returned to Center of reversed positions of the main valve elements Valve Element Open and One Closed Position After Breaking Circuit to Pilot Solenoids INSTALLATION NOTES Pneumatic equipment should be installed only by persons trained and experienced in the installation of pneumatic equipment Air Lines Before installing a ROSS double valve in an existing system the air lines must be blown clean of all contaminants Experience has shown that one of the leading causes of lockouts is foreign material from the air lines which becomes lodged in the valve It is strongly recommended that an air filter be installed ahead of and close to the valve ROSS recommends a 5 micron rated filter Valve Inlet 1 See Figure 8 DO NOT RESTRICT THE AIR SUPPLY Any restriction of the air supply lines for example sharp bends or undersize lines will reduce the speed with which the outlet volume is pressurized See Inadequate Air Supply page 6 for further discussion Valve Outlet 2 For faster pressurizing and exhausting of the outlet volume put the valve close to the mechanism being operated Also any restriction in the outlet lines will reduce pressurizing and exhausting speeds ROSS Valve Exhaust 3 DO NOT RESTRICT THE EXHAUST Limiting the exhausting speed decreases an important safety feature of the double valve During a malfunction in which only one of the valve elements has
15. TEST PROCEDURE ROSS valves are tested after assembly to assure proper operation but it is recommended that the following tests be made when the valve is initially installed or whenever the valve has been disassembled These tests should be made at the repair bench and at the installation At the installation take normal press operation safety precautions during these tests to avoid the potential for human injury or damage to equipment All tests should be performed only by persons trained and experienced in the testing of pneumatic equipment These tests call for the use of the manual overrides If your valve is not so equipped use the corresponding solenoids instead This will require wiring the solenoids so that they can be individually energized Ifthe valve fails any of these tests refer to Troubleshooting beginning on page 5 1 Remove the silencer Apply compressed air in the 30 to 125 psig 2 to 8 5 bar range to inlet port 1 see Figure 8 There should be no pressure at outlet port 2 or exhaust port 3 2 Connect outlet port 2 to a small volume 25 50 cubic inches fitted with a damped pressure gauge Simultaneously energize both pilot solenoids Inlet and outlet pressures should be equal There should be no leakage at the exhaust port De energize both solenoids 3 Simultaneously energize both pilot solenoids then depress manual override N Figure 8 De energize both solenoids while holding override N depressed There should
16. THE WARRANTY DESCRIBED ABOVE OR THE USE OR MISUSE OF THE PRODUCTS NO STATEMENT OF ANY REPRESENTATIVE OR EMPLOYEE OF ROSS MAY EXTEND THE LIABILITY OF ROSS AS SET FORTH HEREIN Printed in the U S A Rev 04 12 2012 ROSS CONTROLS All Rights Reserved Form SM043 ROSS CONTROLS ROSS CONTROLS ROSS CONTROLS ROSS CONTROLS
17. alls below the allowable operating range the electrical supply is inadequate even though the supply voltage might be correct when the solenoids are not energized A voltage that exceeds the allowable maximum can cause premature solenoid burnout loss of air gap due to impact damage or a stuck solenoid plunger See Repair Procedure C below FAULTY SOLENOID OPERATION Before removing solenoids for inspection check to see if the pilot cover is loose A loose cover can prevent full travel of one or both pilot valves However the valve can operate normally if manual actuation is used because the manual pressure pushes the solenoids down into their correct positions If cover is not loose shut off electrical power to the solenoids remove pilot cover slip wires off solenoid terminals and remove solenoids Check for the following Jammed solenoid plunger Great overheating or delamination of the plunger can cause it to jam Such a solenoid must be replaced Defective solenoid coil Check resistance of each coil with an ohmmeter The coil is defective if resistance is zero or infinite The most common cause of solenoid burnout is incorrect supply voltage See Repair Procedure B lf the coils are not defective examine the solenoids for the conditions described below Broken shading coil See S Figure 9 s 16 Copper shading coils reduce the solenoid s wos tendency to buzz when operated on alternating current If a shading coil is loose i i5 or broken
18. d what happens when a malfunction occurs CONDITIONS AT START Inlet air is blocked from the outlet port by two normally closed valve elements A and B see Figure 1 The outlet port 2 is connected to the exhaust port 3 Pilot supply air comes from the inlet port 1 and is carried via passage 4 to the two 3 2 normally closed solenoid controlled pilot valves F SOLENOIDS ENERGIZED Simultaneously energizing the two solenoids a and b Figure 2 causes the two pilot poppets E to shift This closes the pilot exhaust passages and opens the pilot supply passages Pilot air can then go to the main valve pistons J via passages 5 Pressure on the pistons shifts the main valve elements This closes off the exhaust port 3 and connects the inlet port 1 to the outlet port 2 via the crossflow passages 10 and 11 b With the main valve inlet poppets U and V open the monitoring passages 6 are open to inlet pressure This pressure is directed to both ends of spool W Because these monitoring signal pressures are equal spool W remains in its center position Note that the valve elements must move simultaneously in order for the E P spool to remain in its pressure balanced center position e r cu m SOLENOIDS DE ENERGIZED Simultaneously de energizing solenoids a and b allows the two pilot poppets
19. eaned with a water soluble detergent solution If a silencer other than the ROSS silencer supplied with the valve is used be sure that it is of the correct capacity Otherwise excessive back pressure may be immediately present and cause sluggish operation of the valve If a valve locks out intermittently but performs normally when the silencer is removed clean the silencer or replace it with one of the correct capacity Figure 13 Silencer www rosscontrols com 7 ROSS GLOBAL Reach with a LOCAL Touchs ROSS CONTROLS ROSS EUROPA GmbH Troy MI U S A Langen Germany Telephone 1 248 764 1800 Telephone 49 6103 7597 0 Fax 1 248 764 1850 Fax 49 6103 74694 In the United States Email info rosseuropa com Safety Department 1 248 764 1816 www rosseuropa com Customer Service 1 800 GET ROSS 438 7677 Technical Service 1 888 TEK ROSS ROSS ASIA K K 835 7677 Kanagawa Japan www rossconirois com Telephone 81 427 78 7251 Fax 81 427 78 7256 ROSS UK Ltd www rossasia co jp Birmingham United Kingdom Telephone 44 121 559 4900 Fax 44 121 559 5309 ROSS CONTROLS CHINA Ltd Email sales rossuk co uk Shanghai China Telephone 86 21 6915 7951 Fax 86 21 6915 7960 www rosscontrolschina com ROSS SOUTH AMERICA Ltda Sao Paulo Brazil CEP 09725 020 Telephone 55 11 4335 2200 Fax 55 11 4335 3888 Email vendas ross sulamerica com br is ea INDIA Pvt Ltd Telephone 91 44 26
20. igure 12 appears on a label attached to the solenoid cover The voltage at the solenoid terminals should fall within this range during actuation To check remove monitor cover and c attach voltmeter leads to terminals K 8 and 9 Note the voltage during pD W L b actuation of the solenoid 6 INT J If the voltage falls below the allowable PA range the solenoid may fail to reset the lockout switch L Excessive voltage especially if applied for an extended period can lead to solenoid burnout See Repair Procedure below to check for solenoid burnout RESET SOLENOID WILL NOT RESET A burned out reset solenoid cannot return the reset switch to its normal position and the valve remains locked out To check for burnout turn off the electrical power to the reset solenoid Remove the cover of the monitor and attach ohmmeter leads to terminals 8 and 9 An infinite reading indicates a burned out solenoid which must be replaced FAULTY SEALS ON MONITOR SPOOL Faulty seals D on spool W Figure 12 can allow leakage of monitoring air pressures This can result in either nuisance lockouts or failure of the E P monitor to lockout when it should thus creating the potential for personal injury or damage to equipment To remove the spool for inspection first shut off electrical power to the solenoids Then shut off exhaust and lock out the air supply Proceed as follows 1 Remove cover from monitor 2 Remove pin X retaining ring RA and end plug
21. ilot solenoids a and b kept open by switch L see Figure 3 the pilot poppets E and the main inlet poppets U and V return to their normally closed positions see Figure 7 and inlet pressure is completely blocked from the outlet port However if a valve element remains open or partially open outlet pressure remains at two per cent or less of inlet pressure This small outlet pressure is due to the blocking action of spools SA and SB plus the large exhausting capacity of the valve pressure at outlet port 2 does not exceed two per cent b a of inlet pressure i m At the same time inlet air pressure to spool W via B A te A passages 6 will be delivered only from the open valve F n element A The pressure delivered to the right end of the Ah spool will cause it to shift to the left In so doing the spool 2 7 1 lt will trip switch L This will break the electrical circuit to i SG 5 the pilot solenoids a and b so that the valve is locked oy ef e out Further valve operation is inhibited and normal SB EE Se 10 valve operation cannot be resumed until the E P monitor iamen Y is reset See page 4 for important resetting procedures aaa 6 Note that the lockout described above also holds true w when spool W is shifted in the opposite direction because
22. noss Service Manual eS IODULNOI SSOH SERPAR DOUBLE VALVES with E P MONITOR eS IODULNOI SSOH TABLE OF CONTENTS Page NORMAL OPERATION ssssssssssssssssessssesssssssssnesssnessseessnessssesseessanes 2 E P MONITOR LOCKOUT AND RESET ssssssssssssssesssse snssssne os 2 3 CONDITIONS RESULTING FROM A MALFUNCTION 0000 sss 3 INSTALLATION NOVES cissecisessssssnssscctassasivasivcnssecosacenssccentcsseisivates 3 4 TEST PROCEDURE insito neisiet edissa 4 MAINTE NAINGE sctscascessstcssascnsensesisecatisanscassiaieginesasinsbenseidicsnactasntetanat 4 TROUBLESHOOTING sscisssctsscs tessisanssssvertsventacicsnstanserssvadecuecsanecavuesiais 5 REPAIR PROCEDURES ssssssssssssssss ssssssesssnssessnsersueessunssssessnan 6 7 WARRANTY issiima iaia 8 The two main valve elements in the SERPAR double valve move simultaneously during normal operation If the valve elements fail to move simultaneously the E P monitor is designed to detect this condition The monitor reacts by disconnecting the electrical supply to the pilot valve solenoids so that further valve operation is inhibited The valve is then said to be locked out and cannot return to normal operation until the monitor is reset A lockout is not necessarily an indication that the valve has become faulty Rather it is an indication that the monitor has detected non simultaneous movement of the main valve elements and that there is a condition in the system tha
23. nstallation for servicing However turn off the electrical power to the valve shutoff the air supply and exhaust the air in the system before beginning any disassembly operation 4 2012 ROSS CONTROLS All Rights Reserved TROUBLESHOOTING The SERPAR double valve with E P monitor is designed to monitor the outlet pressures of the main valve elements If the valve elements fail to move simultaneously the monitor is designed to detect this condition act to shut down the valve and thus inhibit further operation Such a lockout is not necessarily an indication that the valve is faulty Rather it indicates that the monitor has detected incorrect movement of the main valve elements and that there is a condition in the system that needs correcting Troubleshooting involves finding and correcting the condition that caused the lockout Troubleshooting should be done only by persons trained and experienced in the servicing of pneumatic equipment If the trouble shooting is done at the installation instead of the repair bench take normal press operation safety precautions to avoid possible injury or damage to equipment The chart below can serve as a guide to locating and correcting malfunctions After the valve is repaired it should be tested by following the Test Procedure on page 4 If valve operation is still abnormal repeat the troubleshooting procedure or call ROSS Technical Services department in the U S A at 1 888 TEK ROSS 835
24. oid Circuit Completed Solenoid Circuit Completed Dual Input Valve When the valve is installed the Common line is connected to terminal 3 Solenoid A Input is connected to terminal 1 and Solenoid B Input is connected to terminal 5 With Switch L in its normal position the pilot solenoids are energized when solenoid input power is supplied to Solenoid A Input and Solenoid B Input Warning The wiring in the dual input product as depicted in Figures 4a and 5a must be connected as shown Using a single input or connecting inputs other than as indicated could result in personal injury and or property damage Single Input Valve lt When the valve is installed the Common line is connected to terminal 3 8 and Solenoid Input is connected to terminal 1 Pilot solenoids a and b are factory wired in parallel through switch L With Switch L in its normal position the pilot solenoids are energized when solenoid input power is supplied Warning The wiring in the single input product depicted in Figures 4b and 5b must be connected as shown Using more than one input or connecting the input other than as indicated could result in personal injury and or property damage The E P monitor is designed to respond to non simultaneous movement of the main valve elements and to render the valve inoperable when such movement occurs RESET SOL RESET SOL Figure 5a Dual Input Wiring Figure
25. r at either the outlet or exhaust port Turn off the electrical supply to the pilot solenoids 8 Repeat step 5 9 Re install the silencer The valve is now ready for normal operation Manual overrides Reset Solenoid Inlet Port 2 Outlet Port Exhaust Silencer Electrical Conduit Port Figure 8 External Ports and Overrides MAINTENANCE Pneumatic equipment should be maintained only by persons trained and experienced in the maintenance of such equipment Supply Clean Air Foreign material lodging in valves is a major cause of breakdowns The use of a 5 micron rated air filter located close to the valve is strongly recommended The filter bowl should be drained regularly and if its location makes draining difficult the filter should be equipped with an automatic drain Check Lubricator Supply Rate A lubricator should put a fine oil mist into the air line in direct proportion to the rate of air flow Excessive lubrication can cause puddling in the valve and lead to malfunctions For most applications an oil flow rate in the lubricator of one drop per minute is adequate Note that the double valve does not itself require airline lubrication See below for information about lubricants that are compatible with the materials used in the double valve and are suitable for use in compressed air systems Compatible Lubricants Although this valve does not require air line lubrication it may be used with lubrica
26. s Section of Pilot Assembly Figure 11 Cross Section Valve Body Assembly 6 2012 ROSS CONTROLS All Rights Reserved REPAIR PROCEDURES To disassemble for cleaning follow the steps given in Repair Procedure E Use a water soluble detergent for cleaning varnished areas Avoid chlorinated solvents trichloroethylene for example and abrasive materials The former can damage seals and poppets and abrasives can do permanent damage to metal parts While the valve is disassembled also inspect the piston poppets J for damage See Repair Procedure G Lightly lubricate moving parts and reassemble the valve LEAKING PISTON POPPET SEAL A worn or damaged piston seal BB Figure 11 can allow pilot pressure to leak by the piston and cause erratic valve action and intermittent lockouts Disassemble to inspect seals See Repair Procedure E for disassembly instructions When installed a piston seal should have some compression in the bore It is advisable at this time also to inspect for varnish deposits and wear or damage to poppets and their seats Replace any worn or damaged parts If any parts show signs of deterioration incompatible lubricants or solvents may be the cause See paragraphs on compatible lubricants and cleaning on page 4 Lightly lubricate moving parts and reassemble valve INCORRECT VOLTAGE AT RESET SOLENOID The operating voltage range for the reset solenoid C F
27. t needs correction The SERPAR double valve with E P monitor consists of three interconnected assemblies see below eeeeeeeeces eeeee eeees3 s565c6ueeees357e es5eee eesqeeses sgeeeeee Pilot Assembly Consists of two 3 2 normally closed solenoid controlled pilot valves in a single housing Each pilot valve controls one of the valve elements in the valve body assembly eoceovoceoevoeeeeeeeeeee eee eee eee eo eee ee 8 POSS E P Monitor Assembly Contains a pressure controlled spool an electrical two position momentary latching switch and a reset solenoid eeeesce amp cc5ceeeese sce amp eeeescs8 sc eeoee0eH s54_4seeneseew we eeseseee8ete Valve Body Assembly The valve body has parallel flow paths including two in to out crossflow paths The two main valve elements are 3 2 normally closed poppet valve elements plus spool elements that control air flow through the crossflow passages A silencer is bolted directly to the exhaust port eeeeeees ueee0ne0ee30eonrvoee3eoee0e0e0neoe0ee3eeoeeve3uaeweo3s5ve3eo0e7ee Consider it z W W am 2 sad W a ROSS CONTROLS ROSS CONTROLS ROSS CONTROLS ROSS CONTROLS NORMAL VALVE OPERATION Becoming thoroughly familiar with the functions of the SERPAR double valve and its E P monitor will help in analyzing lockouts and finding their causes The next few pages should be studied carefully to get an understanding of both the normal valve operation an
28. ted air being supplied to other mechanisms Some oils contain additives that can harm seals or other valve components and so cause the valve to malfunction The best oils to use are those specifically compounded for air line service These are generally petroleum base oils with oxidation inhibitors an aniline point between 180 F 82 C and 220 F 104 C and an ISO 32 or lighter viscosity Cleaning the Valve If the air supplied to the valve has not been well filtered the interior of the valve may accumulate dirt and varnish which can affect the valve s performance Although very tolerant of dirty air the valve may sometimes need cleaning COMPATIBLE LUBRICANTS Brand Name American Industrial Oil 32 Amoco Spindle Oil C Amolite 32 Pacemaker 32 Spinesstic 22 Teresstic 32 Velocite 10 Air Lube 10H NR Turbo T32 Sunvis 11 Sunvis 722 Regal R amp O 32 Union Turbine Oil To clean the valve use any good commercial solvent or kerosene Do not use a chlorinated solvent or abrasive materials The former damages seals and abrasives can do permanent damage to metal parts Before reassembling the valve lubricate all sliding surfaces with a grease such as MobilGrease 28 Electrical Contacts In the electrical circuits associated with the valve solenoids keep all switches or relay contacts in good condition to avoid solenoid malfunctions Replace Worn Components In most cases it is not necessary to remove the valve from its i
29. the solenoid must be replaced Wear that causes a loss of air gap There must be a small gap between the Figure 9 Solenoid solenoid plunger and the field frame when the solenoid is energized See air gap 15 Figure 9 If significant wear is apparent in areas 16 the air gap can be lost and the solenoid will buzz loudly when energized With this much wear the solenoid should be replaced Lubrication will help to prolong solenoid life by preventing some of the above troubles Solenoids should be lubricated periodically with an NLGI 2 grease Put grease on the plunger and all impact surfaces FAULTY PILOT INSERT Shut off electrical power to solenoids shut off exhaust and lock out the air supply Disassemble pilot section in the following way 1 Remove pilot cover Q Figure 10 Slip leads off solenoid tab terminals and lift out solenoids To check solenoids see Repair Procedure C Remove rubber cushions CA from tops of inserts With Truarc type pliers remove retaining rings CB Remove inserts by grasping them at the shoulder area and pulling with a circular motion Removing inserts by pulling on the spring or stem may damage the inserts 6 Be sure that poppet return springs CC are removed Check action of each insert The Q stem should move easily with light F s i a a oN CA finger pressure and should not ca F jerk or grab during its travel about En cB
30. y after resetting the E P monitor the electrical supply to the pilot solenoids must be turned off during the resetting process Otherwise the energized solenoids will actuate the valve as soon as the monitor is reset After the pressure imbalance on the spool of the E P monitor has been removed the spool is returned by springs M to its normal center position However switch L remains in its shifted position and the valve remains locked out The cause of the lockout must be corrected before resetting switch L and thereby allowing the valve to be actuated Reset is accomplished by briefly energizing the reset solenoid C IMPORTANT Energize the reset solenoid only briefly Prolonged energization of the reset solenoid can cause it to burnout Thus the monitor can no longer be reset and the valve will remain locked out VALVE CONDITIONS RESULTING FROM A MALFUNCTION DURING A MALFUNCTION If conditions do not allow one of the main valve elements to be shifted or do not allow one of the elements to return to its normally closed position upon de actuation we have the condition depicted in Figure 6 one valve element closed and one open Inlet air flowing past open poppet U and into crossflow passage 10 is substantially blocked by spool SB on valve element B Although some air can pass around the spool SB the amount is so small and the exhausting capacity of the valve so large that the FOLLOWING LOCKOUT With the electrical circuit to p

Serpar Double Valves with E-p Monitor

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