Eaton AMH-4.76-VR, Instruction Book

Page 1: ...March 2016 Instruction Book IB182023EN AMH 4 76 VR Replacement Circuit Breaker Supercedes October 2013 Effective AMH 4 76 VR 4 76 1200A Shown...

Page 2: ...office should be consulted Sale of the product shown in this literature is subject to the terms and conditions outlined in appropriate Eaton selling policies or other contractual agreement between Ea...

Page 3: ...BLOCK 13 4 7 INTERLOCKS 13 4 7 1 ANTI CLOSE INTERLOCK 13 4 7 2 RACKING SYSTEM TRIP AND SPRING RELEASE INTERLOCKS 13 4 8 MISCELLANEOUS ITEMS 15 4 8 1 MOC OPERATOR 15 4 8 2 OPERATIONS COUNTER 15 SECTION...

Page 4: ...K RESPONSE CODE VR Series circuit breakers have a quick response code QR Code on the escutcheon of the circuit breaker cover This QR Code is a matrix barcode that provides direct access to download VR...

Page 5: ...VR Replacement Circuit Breaker E H I G F J H D B C C A Table 2 AMH 4 76 VR Dimensions Breaker Type Existing Breaker Rated Continuous Current at 60 Hz Amps A B C D E F G H I J AMH 4 76 VR 250 250U 120...

Page 6: ...nd or property damage Do not work on a breaker with the secondary test coupler engaged Failure to disconnect the test coupler could result in an electrical shock leading to death personnel injury and...

Page 7: ...eaker Style 94C9506G01 Racking Handle The racking handle is used to drive the racking mechanism which moves the circuit breaker into and out of the cell The original OEM racking handle will interface...

Page 8: ...nual trip button The breaker will trip as shown by the breaker contacts open green indicator After completing this initial check leave the closing springs discharged and breaker contacts open Outdoor...

Page 9: ...ont External View of AMH 4 76 VR Front External View 1 Manual Charging Socket 5 Guide Bar 9 MOC Actuator 2 Push To Close Button 6 Breaker Contacts Indicator 10 Push To Open Button 3 Racking Access Doo...

Page 10: ...Replacement Circuit Breaker Figure 3 4 Rear External View of AMH 4 76 VR Rear External View 1 Shutter Actuator 4 SURE CLOSE Spring 7 Secondary Disconnect 2 Primary Disconnect 5 Guide Rail 8 Ground Con...

Page 11: ...he vacuum to be quickly restored and prevents the transient recovery voltage from causing a restrike across the gap of the open contacts 4 1 1 THE INTERRUPTER ASSEMBLY Each interrupter is assembled at...

Page 12: ...r positions shown in Figure 4 6 as follows a Breaker open closing springs discharged b Breaker open closing springs charged c Breaker closed closing springs discharged d Breaker closed closing springs...

Page 13: ...ely retrofitted breakers Consequently it prevents the breaker from closing automatically even though the control close contact may have been made while the breaker is racked to the CONNECTED position...

Page 14: ...een Test and Connect positions OPERATION C and NO C and NC C and NO C and NO C and NC C and NO Brown Switch Black Switch Black Switch Brown Switch SWITCH TERMINAL LS1 bb LS2 aa LS2 bb LC PS1 PS2 Break...

Page 15: ...e breaker s MOC operator interfaces with the cell MOC switch in the same manner as the original breaker being replaced All VR Series breakers which are supplied with MOC operators are engineered with...

Page 16: ...t Front Faceplate Removed 18WR Vacuum Element 1 LH Closing Spring 5 Spring Release Assembly 9 Manual Charge Socket 2 Motor Cutoff Switch 6 Shunt Trip Assembly 10 Ratchet wheel 3 Latch Check Switch Rea...

Page 17: ...Spring Release Close Latch 6 Ratchet Wheel 11 Anti Close Interlock 2 Pole Shaft 7 Spring Crank 12 Motor Ratchet Lever 3 Closing Spring Fixed End 8 Cam Shaft 13 Spring Release Close Clapper 4 Closing...

Page 18: ...g Spring Discharged 4 9 c Breaker Closed and Closing Spring Discharged 4 9 b Breaker Open and Closing Spring Charged 4 9 d Breaker Closed and Closing Spring Charged Charging Schematic 1 Main Link Roll...

Page 19: ...he cell Maintenance usually means cleaning and lubricating the MOC mechanism If the MOC has seen a large number of cycles however worn components may have to be replaced To insure the proper operation...

Page 20: ...an audible click and the springs Charged Discharged Indicator shows Charged Remove the maintenance tool NOTICE IF THE SPRINGS ARE TO BE CHARGED ON A CLOSED BREAKER NO CLICK IS HEARD AT THE END OF CHAR...

Page 21: ...ndicator reads OPEN d Push the circuit breaker into the cell until the mechanical stop is reached this will be indicated by an audible click At this point the side plunger has fallen into the front sl...

Page 22: ...the breaker can be operated either electrically or mechanically Remove rotary racking handle before performing any testing b To further remove the breaker to the disconnect position continue turning...

Page 23: ...ted Withstand 1125V 60Hz For 1 Minute Hipot Tester Clean And Retest Or Replace 2 Power Element Vacuum Interrupters Contact Erosion Visibility Of Mark Visual Close The Breaker And Look For Green Mark O...

Page 24: ...ential test is recommended a DC test may be performed if only a DC test unit is available but is not recommended In this case the equipment must be capable of delivering 5 milliamperes for one minute...

Page 25: ...the primary circuit Open the breaker Connect the high potential lead of the test machine to one of the poles of the breaker Connect the remaining poles and breaker frame to ground Start the machine w...

Page 26: ...nergy available in terms of over travel in inches to close the breaker contacts to their full extent It may be used periodically to monitor the health of the mechanism General Information The CloSure...

Page 27: ...uit breaker then close it then reopen it Verify that the mark made in Step 7 is aligned with the pen opening If it is not aligned this indicates a problem with the circuit breaker stop the test and co...

Page 28: ...Sharpie 15o Left and Right Figure 6 13 Top view of Cam and Marker Interface Cam Marker CloSure Tool TM 15O 15O Figure 6 10 With Marker in Hole C While Closing Breaker Figure 6 8 Manually Charging Clo...

Page 29: ...cam shaft the main link and the motor eccentric These bearings are packed at the factory with a top grade slow oxidizing grease which normally should be effective for many years They should not be dis...

Page 30: ...Cut Off Contacts Open Or Burned Trip Coil Assembly Clapper Fails To Reset Closing Sound But No Close Pole Shaft Not Open Fully Trip Latch Reset Spring Damaged Or Missing Trip Bar D Shaft Fail To Rema...

Page 31: ...Breaker Auxiliary Switch 94C9525G13 5 BREAKER POSITION SWITCH Breaker Position Switch PS1 94C9525H06 6 BREAKER POSITION SWITCH Breaker Position Switch PS2 94C9525H07 7 LATCH CHECK SWITCH Latch Check...

Page 32: ...levard Cleveland OH 44122 United States Eaton com 2013 Eaton All Rights Reserved Printed in USA Publication No IB182023EN March 2016 Eaton is a registered trademark All trademarks are property of thei...