Eaton 75VCPW-VSR Instruction Book

Contents

17Instruction Book IB02707112EAugust 201550/75VCPW-VSRBreaker To Vacuum Starter Replacement UnitEATON CORPORATION www.eaton.comTablt 5.3. RtcNmmtndtd TNrqut ValutsDiameter (mm) Torque N-m Bolt Size lb-in.4 2.8 - 3.1 8 - 32 245 5.6 - 6.2 10 - 32 366 9.4 - 10.4 .25 - 20 728 22.9 - 25.4 .31 - 18 14410 45.5 - 50.6 .38 - 16 30012 79.2 - 88.0 .50 - 13 540Note:N Recommended Torque Values unless otherwise specified.5.4 VACUUM INTEGRITY CHECK WARNINGTHIS PROCEDURE REQUIRES THE USE OF A HIGH POTENTIAL TEST UNITWHICH PRODUCES HAZARDOUS VOLTAGES.APPLYING HIGH VOLTAGES ACROSS THE OPEN CONTACTS OF AVACUUM INTERRUPTER MAY PRODUCE X-RAYS. THE RADIATION MAYINCREASE WITH AN INCREASE IN THE VOLTAGE OR A DECREASE IN THEDISTANCE BETWEEN THE OPEN CONTACTS. THE LEVELS OF RADIATIONGENERATED AT THE RECOMMENDED TEST VOLTAGES AND NORMALCONTACTOR OPEN GAP SPACING ARE EXTREMELY LOW. HOWEVER, AS APRECAUTIONARY MEASURE IT IS RECOMMENDED THAT ALL OPERATINGPERSONNEL STAND AT LEAST THREE FEET AWAY FROM THE CONTACTORWHILE PERFORMING THIS TEST.Vacuum starters depend on the vacuum in each interrupter tosuccessfully stop current flow to the connected load when thestarter opens.Starters are thoroughly tested at the factory prior to shipment. Theycan, however, be damaged by improper handling during shipmentand storage. The integrity of the vacuum interrupters shouldtherefore be verified before the contactor is energized for the firsttime. The check should also be made each time the contactor isserviced or repaired, otherwise the test should be performed each50,000 operations or annually, whichever occurs first.To verify the integrity of the vacuum interrupters a voltage of19kV-ac should be applied across the open contacts of theinterrupters. The voltage should be applied for 60 seconds withoutbreakdown. Breakdown is defined as a current of 5mA or moreflowing across the open contacts. Note that approximately 1mA ofcurrent will flow through each interrupter during the AC test due tothe capacitance of the vacuum interrupter.If a DC high potential test unit is used, make certain that the peakvoltage does not exceed 28kV, the peak of the corresponding ACRMS test voltage. A megger cannot be used to verify vacuumintegrity due to its limited output voltage.5.5 INSULATION INTEGRITY CHECKPRIMARY CIRCUIT:The integrity of primary insulation may be checked by the AC highpotential test. The test voltage is 15kV, RMS, 60Hz. Conduct the testas follows:Close the starter. Connect the high potential lead of the testmachine to one of the phases of the starter. Connect the remainingtwo phases and starter frame to ground. Start the machine withoutput potential at zero and increase to the test voltage. Maintainthe test voltage for one minute. Repeat for the remaining phases.Successful withstand indicates satisfactory insulation strength of theprimary circuit.Open the starter. Connect the high potential lead of the testmachine to one of the poles of the starter. Connect the remainingpoles and starter frame to ground. Start the machine with outputpotential at zero and increase to the test voltage. Maintain thetest voltage for one minute. Repeat for the remaining five poles.Successful withstand indicates satisfactory insulation strength of theprimary circuit.If a DC high potential machine is used, make certain that the peakvoltage does not exceed the peak of the corresponding AC RMS testvoltage.SECONDARY CIRCUIT:Connect all points of the secondary disconnect pins with a shortingwire. Connect this wire to the high potential lead of the testmachine. Ground the starter frame. Starting with zero, increase thevoltage to 1125 RMS, 60 Hz. Maintain the voltage for one minute.Successful withstand indicates satisfactory insulation strength of thesecondary control circuit. Remove the shorting wire.5.6 INTERRUPTING WEAR CHECKThe interrupters used in the starter are designed for long electricallife. Replacement should be at 300,000 operations except incases of plugging or jogging which may require more frequentreplacement. Verification of contact wear can be made by followingthe procedure below.The overtravel gap for a new starter is .080” and is set at thefactory. As the contacts wear the overtravel is reduced. The SLinterrupter design allows for .080” wear before replacement isrequired. To verify that the contacts are not worn beyond theirallowable limits, close the contactor with rated control power. Insertthe .020” contactor wear gauge, p/n 5259C11H01, between theoperating plate and the washer on the lower insulator stem of eachpole. Refer to Figure 5.3. If the gauge cannot be freely insertedon each pole, all three interrupters must be replaced. Refer to thesection 6 for instructions on replacing the interrupters.Figurt 5.3. Inotrrupotr Wtar Chtck5.7 CONTACT RESISTANCE CHECKTesting that measures the contact resistance of the vacuuminterrupters is not recommended since the results can vary widelyon good contacts. If a resistance check is performed, the bestresults will be with a test module that will force 10 amps throughthe contacts while measuring resistance. The resistance should notexceed the factory test levels by more than 15%.Note:N Do not use a 100 Amp source. Test sets with output exceeding 10Amps can damage the fuse elements5.8 ELECTRICAL OPERATIONS CHECKAfter going through the above steps, the starter is now ready to beoperated electrically. It is preferred that this check be made with thestarter in the Test position in the switchgear compartment.Since the Type VCPW-VSR Vacuum Motor Starter ReplacementUnit is for use in existing VCP-W Metal-Clad Switchgear, installation