Eaton VR+ Series Instruction Book

Contents

20 Instruction Book IB182923EN September 2018 www.eaton.comAMH-4.76-VR+VR-Series+ Replacement Circuit BreakerSECTION 5: INSPECTION & INSTALLATIONm WARNINGBEFORE PLACING THE CIRCUIT BREAKER IN SERVICE, CAREFULLY FOLLOWTHE INSTALLATION PROCEDURE BELOW AND THE SAFE PRACTICES SETFORTH IN SECTION 2. NOT FOLLOWING THE PROCEDURE MAY RESULT ININCORRECT CIRCUIT BREAKER OPERATION LEADING TO DEATH, BODILYINJURY, AND PROPERTY DAMAGE.When the circuit breaker is first commissioned into service and eachtime the circuit breaker is returned to service, it should be carefullyexamined and checked to make sure it is operating correctly.5.1 EXAMINATION FOR DAMAGEExamine the cirucit breaker for loose or obviously damaged parts.Never attempt to install nor operate a damaged circuit breaker.5.1.1 NAMEPLATE VERIFICATIONVerify the information on the new VR-Series+ nameplate matchesthe information on the purchase order. If any discrepancies exist,notify Eaton’s Electrical Engineering Services & Systems forresolution prior to proceeding.m WARNINGALWAYS DE-ENERGIZE/ISOLATE THE POWER SOURCE FEEDING THEPOWER CIRCUIT BREAKERS/SWITCHGEAR AND LOCK-OUT/TAG-OUT THEPOWER SOURCE PRIOR TO INSERTION OR REMOVAL OF ANY POWERCIRCUIT BREAKER. NEVER ATTEMPT TO MAINTAIN OR MODIFY A CIRCUITBREAKER WHILE INSERTED IN A SWITCHGEAR CELL STRUCTURE. ALWAYSREMOVE THE POWER CIRCUIT BREAKER AND MOVE IT TO A SUITABLEAREA FOR MAINTENANCE OR REPAIR.FOLLOW ALL LOCKOUT AND TAG-OUT REQUIREMENTS OF THE NATIONALELECTRIC CODE, OSHA AND ANY OTHER APPLICABLE LOCAL CODES,REGULATIONS AND PROCEDURES.5.2 SURE CLOSE MECHANISM ADJUSTMENTm WARNINGFOR ALL TYPE CIRCUIT BREAKER HOUSINGS EQUIPPED WITH MECHANISMOPERATED CELL (MOC) SWITCHES, THE STEPS OUTLINED IN THIS SECTIONMUST BE PERFORMED BEFORE INSTALLING A REPLACEMENT VR-SERIES+CIRCUIT BREAKER. FAILURE TO COMPLY COULD CAUSE SEVERE PERSONALINJURY, DEATH, EQUIPMENT DAMAGE AND/OR IMPROPER OPERATIONAll type AMH-4.76-VR+ breakers utilize the AMH-4.76-VR+ SURECLOSE mechanism to control kinetic energy transfer and closelymimic the dynamics and velocities of older circuit breakers. It isimperative that this mechanism be adjusted to compensate for theforce of the MOC switch mounted in the cell.The circuit breaker has been factory adjusted to operate onemechanism operated cell (MOC) switch in the cell. This means thatfor applications with either no MOC switch or one MOC switch, nofield adjustments are required.Finally, the SURE CLOSE mechanism provides an effective way toevaluate the condition of the MOC in the cell. If the SURE CLOSEdrive spring is properly adjusted, but the MOC does not fully openor close, it is time to maintain the MOC in the cell. Maintenanceusually means cleaning and lubricating the MOC mechanism.If the MOC has seen a large number of cycles, however, worncomponents may have to be replaced.To insure the proper operation of the SURE CLOSE mechanism, theMOC assembly should be cleaned and inspected for worn parts andthen lubricated. A spring force gauge should be used to measure theforces needed to move the switch to the fully closed position priorto inserting the circuit breaker. The differential force of the assemblyand the circuit breaker should be a minimum of 10 lbs. with thecircuit breaker having the higher recorded force. Should the forcesbe less than that, proceed with the following steps to increase thecircuit breaker force:m WARNINGMEASUREMENTS AND ADJUSTMENTS SHOULD NEVER BE ATTEMPTEDIN AN ENERGIZED STRUCTURE. IF THE STRUCTURE CAN NOT BEDE-ENERGIZED, THEN PROPER PERSONAL PROTECTIVE EQUIPMENTPER NFPA 70E MUST BE WORN AT ALL TIMES WHILE GATHERING MOCSWITCH DATA, ADJUSTING OR SERVICING THE MOC SWITCH. FAILURE TOCOMPLY WITH THIS WARNING COULD CAUSE SEVERE PERSONAL INJURY,DEATH, EQUIPMENT DAMAGE AND/OR IMPROPER OPERATION.To adjust the SURE CLOSE drive spring for a specific number ofMOC switches, proceed with the following steps:Sttp 1e: Locate the MOC drive spring (Figure 3.3). It is located in theleft lower portion of the circuit breaker as viewed from the rear ofthe circuit breaker.Sttp 2e: From the factory, the drive spring comes set with adequateforce to operate one MOC switch, however, more force can begenerated. Refer to Figure 5.1 to see how that adjustment wouldlook. Notice that there is a nut and a jam nut on the threaded rodto make the adjustment easy.Sttp 3e: Using a spring gauge, measure the force required tooperate the MOC to the fully closed position in the cell at theinterface with the circuit breaker.Sttp 4e: With the breaker out of the cell, close the circuit breakerand measure the output of the MOC drive with a spring gauge.Open the circuit breaker. The MOC drive force should exceed theMOC cell force required by 10 - 15lbs. If not, an adjustment isrequired.Sttp 5e: Loosen the jam nut on the SURE CLOSE spring andcompress the spring an additional .25 inches. Close the circuitbreaker.m WARNINGWITH THE CIRCUIT BREAKER IN THE OPEN POSITION, THE SPRINGCOMPRESSION SHOULD NEVER BE SET TO A DIMENSION LESS THAN 3INCHES AS MEASURED IN FIGURE 5.1.Sttp 6e: Remeasure the MOC output spring force in the closedposition. Repeat until the MOC forces are adequate.Sttp 7e: Insert into the cell.Sttp 8e: Operate the circuit breaker to verify the new setting.Sttp 9e: Repeat steps 3 - 7 until acceptable operation is achieved.Sttp 10e: Anytime an adjustment is made, make sure the newFigurt 5.1. SURE CLOSE Spring Comprtssion Sttting