iii
Instruction Book
IB182023EN March 2016 www.eaton.com
AMH-4.76-VR
Replacement Circuit Breaker
Table of Contents
SECTION 1: INTRODUCTION
4
1.1 VISUAL INSTRUCTION BOOKLET ESSENTIALS
4
1.2 QUICK RESPONSE CODE
4
1.3 AVAILABLE AMH-4.76-VR CIRCUIT BREAKERS
4
SECTION 2: SAFE PRACTICES
6
SECTION 3: RECEIVING, HANDLING, AND STORAGE
7
3.1 RECEIVING
7
3.2 HANDLING
7
3.3 STORAGE
8
3.4 AMH-4.76-VR APPROXIMATE WEIGHTS
8
SECTION 4: DESCRIPTION AND OPERATION
11
4.1 VACUUM INTERRUPTER
11
4.1.1 THE INTERRUPTER ASSEMBLY
11
4.1.2 CONTACT EROSION INDICATOR
11
4.1.3 CONTACT WIPE AND STROKE
12
4.2 PHASE BARRIERS
12
4.3 BUSHINGS AND DISCONNECTING
CONTACT ASSEMBLIES
12
4.4 STORED ENERGY MECHANISM
12
4.4.1 CLOSING SPRING CHARGING
12
4.4.2 CLOSING OPERATION
13
4.4.3 TRIPPING OPERATION
13
4.4.4 TRIP-FREE OPERATION
13
4.5 CONTROL SCHEMES
13
4.5.1 TIMING
13
4.6 SECONDARY CONNECTION 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 5: INSPECTION & INSTALLATION
19
5.1 EXAMINATION FOR DAMAGE
19
5.1.1 NAMEPLATE VERIFICATION
19
5.2 SURE CLOSE MECHANISM ADJUSTMENT
19
5.3 MANUAL OPERATION CHECK
20
5.4 VACUUM INTERRUPTER INTEGRITY
20
5.5 LOW FREQUENCY WITHSTAND
TEST (INSULATION CHECK)
20
5.6 CONTACT EROSION AND WIPE
20
5.7 PRIMARY CIRCUIT RESISTANCE
20
5.8 ELECTRICAL OPERATIONS CHECK
20
5.9 DESCRIPTION OF OPERATIONAL POSITIONS
21
5.10 INSERTION PROCEDURE
21
5.11 REMOVAL PROCEDURE
22
SECTION 6: INSPECTION & MAINTENANCE
23
6.1 INSPECTION FREQUENCY
23
6.2 INSPECTION AND MAINTENANCE PROCEDURES
23
6.3 VACUUM INTERRUPTER INTEGRITY TEST
24
6.4 CONTACT EROSION AND WIPE
24
6.5 INSULATION
25
6.6 INSULATION INTEGRITY CHECK
25
6.7 PRIMARY CIRCUIT RESISTANCE CHECK
26
6.8 MECHANISM CHECK
26
6.8.1 CLOSURE™ TEST
26
6.9 LUBRICATION
29
SECTION 7: REPLACEMENT PARTS
31
7.1 GENERAL
31
7.2 ORDERING INSTRUCTIONS
31
