IMPELLER 3N8214 - Caterpillar

Illustration 1 g00809802
(1) 24 VDC Power Supply 1 (2) 24 VDC Power Supply 2Shutdown Procedure for Single or Dual Input without Maintenance Bypass
If 24 VDC is still available, the service person should perform a "Control X" on the PC in order to brake the rotor. This will ensure that there is no power in the system upon shutdown.
Turn the keyswitch for the System Cabinet to the Bypass position. Make sure that the system is in Bypass mode.
Open the load circuit breaker downstream of the UPS system.
Disconnect incoming power by opening the main circuit breaker that is located upstream from the UPS system.
Allow the capacitor banks to bleed down for approximately 5 minutes in order to dissipate any residual energy in the bus, armature leads, and fuses.Removal of the Power Supply
Illustration 2 g00811061
Open the door to the cabinet for the MMU or SMS in order to gain access to the door for the controller board (3) .
Remove 3 screws (4) that secure the door for the controller board.
Illustration 3 g00811076
Remove the lower hose clamp (8) from the 24 VDC power supply module (9) .
Remove the upper hose clamp (6) from the 24 VDC power supply module and remove the hose (7) .
Remove 2 screws from the front of the power supply vent adapter (10) .
Loosen the screw that is on the back of the power supply vent adapter (10) .Note: Do not remove the screw.
Remove the power supply vent adapter (10) .
Illustration 4 g00811094
Label all the wires on the static switch interface board (11) .
Disconnect the connector for the 24 VDC power supply from "J7" terminal (18) that is located at the rear of the board.Note: Terminal "J7" (18) can not be seen from the front of the unit.
Disconnect the "APC" input/output connector from terminal "J1" (15) that is located at the rear of the board.
Disconnect the External Thermistor connector from the terminal "J9" that is located at the rear of the board.
Disconnect the "A" connector from terminal "J8" (12) .
Disconnect the "A" connector from terminal "J6" (13) .
Disconnect the "B" connector from terminal "J5" (14) .
Disconnect the "B" connector from terminal "J4" (16) .
Disconnect the "C" connector from terminal "J3" (17) .
Disconnect the "C" connector from terminal "J2" (19) .
Remove the 4 mounting screws and remove the board.
Label the power cables on the terminals for the static switch input for the following phases: A, B and C. Label the power cables on the terminals for the static switch output for the following phases: A, B and C.
Disconnect the power cables from each input terminal. Disconnect the power cables from each output terminal. Power cables must be disconnected from the following phases: A, B and C.
Loosen the two mounting bolts at the top of the static switch module.Note: Do not remove the two mounting bolts.
Remove the static switch.
Illustration 5 g00811130
Label all the wires on the assemblies for the power supply.
Disconnect the red wire from terminal "J35" (25) on the "PWD".
Disconnect the black wire from terminal "J46" (26) on the "PWD".
Disconnect the red wire from