MCS Circuit Breaker Replacement

Prerequisites

Table 1. Personnel requirements
Required persons	Preliminary requirements	Procedure	Finalization
1	Not Applicable	15 mins minutes	Not Applicable

Table 2. Tools and test equipment
Item	Quantity	Effectivity	Part number	Manufacturer
Phillips screwdriver	-	-	-	-
Long nose pliers	-	-	-	-
14mm Wrench	-	-	-	-

Table 3. Replacement parts
Item	Quantity	Effectivity	Part number	Manufacturer
Circuit Breaker 5789467	1	-	-	-

Table 4. Safety

Warning

ELECTROCUTION HAZARD!

DANGEROUS VOLTAGES ARE PRESENT AROUND THE MAGNET SUBSYSTEM WHEN ENERGIZED.

LOCK AND TAG OUT POWER TO THE MAGNET ROOM BEFORE STARTING WORK.

Table 5. Required conditions
Condition	Reference	Effectivity
Follow all GEHC Lockout / Tag-out procedures before servicing.	-	-

Disconnect electrical power from the System.
Remove top and side panels of system.
Remove the securing nut from rear panel. See Figure 1

Figure 1. Remove Nut
Remove circuit breaker carefully and note not to damage the wires.
Inspect the crimped termination see Figure 2. If the crimped termination signs of overheating and discoloration（turn to dark yellow or brown), do not go ahead and order system FRU P/N 5364447 to replace it.

Figure 2. Crimped Termination
Remove the two wires form the circuit breaker using long nose pliers by grasping the Fast-on connector with the pliers. See Figure 3

Figure 3. Remove Wires
Replace circuit breaker.
Restore the wires and rear panel with reverse order of procedure.
Check all water connection and electrical connection prior to start chiller.
Restore the power and check leakage.
Note:
TURN OFF SYSTEM IMMEDIATELY WHEN COOLANT LEAKAGE IS DETECTED
- Disconnect electrical power and repair leakage.
- When leakage has been repaired and coolant spills has been cleaned, restore power and test again.
Restore top and side panels.

No finalization steps.