Main Breaker Replacement

Prerequisites

Table 1. Personnel requirements
Required persons	Preliminary requirements	Procedure	Finalization
1	Not Applicable	60 minutes	Not Applicable

Table 2. Tools and test equipment
Item	Quantity	Effectivity	Part number	Manufacturer
Standard Tool	1	-	-	-

Table 3. Replacement parts
Item	Quantity	Effectivity	Part number	Manufacturer
Main Breaker	1	-	Refer to FRU Manual	-

Table 4. Safety

DANGER

ELECTROCUTION HAZARD!

DANGEROUS AND OR FATAL VOLTAGES ARE PRESENT IN THE ENERGIZED CABINET.

Follow LOTO steps as given in first section of this document to disable and verify safe voltage levels.

Table 5. Required conditions
Condition	Reference	Effectivity
PDU and Service Disconnect Panel (or Main Disconnect Panel) must be turned OFF. Refer to Lockout / Tagout for MDP(Main Disconnect Panel) or Facility PDU.	-	-

Remove 6 screws and remove PDU front Panel.

Figure 1. PDU Front Panel
Disconnect 2-pin connector. 2pin connector is located behind the Main Breaker.

Figure 2. 2-pin connector
Perform the following steps.
1. Remove three screws from the main Breaker top terminal and remove cables. Use 5mm hex wrench.
2. Remove three screws from the top of EMI Filter and remove the bus bar.
Figure 3. Remove screws
Notice

When removing Main Breaker, slowly withdraw it not to damage 2 pin connector behind it.
Remove 2 silver screws and remove main breaker.

Note: Do not remove black screws.

Figure 4. Remove main breaker
Replace the busbar and Insulator sheet (Black color). Use 5mm hex wrench for busbar removal.

Figure 5. Busbar and Insulator sheet (Black color)
Compare with the defective Main Breaker and set the overload and short circuit trip dip SW to the correct value corresponding to the input voltage.

Figure 6. DIP SW
Notice

When restoring the Main Breaker, do not forget to connect the two pin connector.
Restore it by the reverse order of the removal.