Eaton VR+ Series Instruction Book

Contents

21Instruction Book IB182923EN September 2018 www.eaton.comAMH-4.76-VR+VR-Series+ Replacement Circuit Breakerm WARNINGKEEP HANDS OFF THE TOP EDGE OF THE FRONT BARRIER WHEN PUSHINGA CIRCUIT BREAKER INTO A CELL. FAILURE TO DO SO COULD RESULT INBODILY INJURY, IF FINGERS BECOME WEDGED BETWEEN THE CIRCUITBREAKER AND THE CELL. USE THE HANDLES PROVIDED ON THE FRONT OFTHE CIRCUIT BREAKER FACEPLATE, OR USE BOTH FULLY OPENED HANDSFLAT ON THE FRONT OF THE FACEPLATE.These checks can be performed with the circuit breaker in itswithdrawn or disconnect position and connecting the circuit breakerto a test cabinet or to the switchgear cell’s secondary receptacleusing the special extension cable designed for this purpose anddescribed in Section 3.Perform electrical operations checks. Close and trip the circuitbreaker electrically several times to verify that the operation isreliable and consistent. Check that the operation of the springcharging motor is reasonably prompt and that the motor makes nounusual noise.m WARNINGDO NOT PERFORM ELECTRICAL OPERATION CHECKS WITH THE CIRCUITBREAKER IN THE “CONNECT” POSITION BECAUSE OF THE POSSIBILITY OFCONNECTING DE-ENERGIZED LOAD CIRCUITS TO THE ELECTRICAL POWERSOURCE, RESULTING IN DEATH, PERSONNEL INJURY OR EQUIPMENTcompressed spring length (measured in the open position) isrecorded if different than the dimension in this instruction book.Sttp 11e: After an adjustment is made, make sure that all nuts aresecured in place, prior to returning to service.5.3 MANUAL OPERATION CHECKManual operational checks must be performed before the circuitbreaker is connected to an energized circuit. Tests must beperformed with the circuit breaker withdrawn from the cell or in thedisconnect position. While the circuit breaker is withdrawn or in thedisconnect position, place the maintenance tool into the manualcharge socket opening and charge the closing springs with about36 up and down strokes of the handle. When charging is complete,the closing crank goes over center with an audible “click” and thesprings Charged / Discharged Indicator shows “Charged”. Removethe maintenance tool.m NOTICEIF THE SPRINGS ARE TO BE CHARGED ON A CLOSED CIRCUIT BREAKER,NO CLICK IS HEARD AT THE END OF CHARGING OPERATION. DISCONTINUECHARGING AND REMOVE THE MAINTENANCE TOOL AS SOON AS“CHARGED” FLAG IS FULLY VISIBLE. CONTINUE ATTEMPTS TO FURTHERCHARGE MAY RESULT IN DAMAGE TO THE MECHANISM.m WARNINGALWAYS REMOVE THE MAINTENANCE TOOL AFTER CHARGING THESPRING. FAILURE TO REMOVE THE MAINTENANCE TOOL FROM THEBREAKER COULD CAUSE INJURY TO PERSONNEL AND/OR EQUIPMENTDAMAGE IF THE BREAKER WAS TO CLOSE.Close and trip the circuit breaker by pushing the close lever then thetrip lever (Figure 3.3).5.4 VACUUM INTERRUPTER INTEGRITYUsing a dry lint-free cloth or a paper towel, clean all the insulatingsurfaces of the pole units. Conduct a vacuum interrupter integritycheck as described in Section 6.5.5 LOW FREQUENCY WITHSTAND TEST (INSULATIONCHECK)Check breaker primary and secondary insulation per Section 6.5.6 CONTACT EROSION AND WIPEManually charge the closing springs and close the circuit breaker.Check contact erosion and wipe as described in Section 6.5.7 PRIMARY CIRCUIT RESISTANCECheck the primary circuit resistance as described in Section 6. Theresistance should not exceed the values specified. Record the valuesobtained for future reference.5.8 ELECTRICAL OPERATIONS CHECKAfter going through the above steps, the circuit breaker is nowready to be operated electrically. It is preferred that this check bemade with the circuit breaker in the Test position in the breakercompartment.Since the Type AMH-4.76-VR+ Circuit Breaker is for use in existingAMH Metal-Clad Switchgear, installation procedures are similar. If itis necessary to reference anything in the breaker compartment, referto the original instruction books supplied with the assembly.m WARNINGEXAMINE THE INSIDE OF THE CELL BEFORE INSERTING THE BREAKERFOR EXCESSIVE DIRT OR ANYTHING THAT MIGHT INTERFERE WITH THECIRCUIT BREAKER TRAVEL.Figurt 5.2. AMH-VR+ in tht Disconntct Position