Replacing a (3NO) Contactor in the Rack Mount 3-Phase Power Distribution Unit
- Updated2025-12-16
- 4 minute(s) read
Replacing a (3NO) Contactor in the Rack Mount 3-Phase Power Distribution Unit
- Power off the ATE Core Configurations Generation 2 by flipping the main disconnect branch breaker to off.
- If your ATE Core Configurations Generation 2 utilizes a UPS to provide backup power, press the power button on the UPS to power it down.
- Disconnect the ATE Core Configurations Generation 2 from facility power.
| Shipping Kit Part Number | Description |
|---|---|
| 789094-01 | 440 V 3-Pole (3NO) Contactor, 24 V to 60 V DC Controlled |
This procedure only applies to ATE-38U, ATE-44U, and ATE-38E racks.
Equipment
- 3 mm hex key
- T10 Torx head screwdriver, 0.76 N · m (6.7 in. · lb)
- T30 Torx head screwdriver, 6.00 N · m (53.1 in. · lb)
- #3 Phillips head screwdriver, 2.49 N · m (22.0 in. · lb)
- #2 Phillips head screwdriver, 1.70 N · m (15.0 in. · lb)
- T8 Torx head screwdriver, 0.76 N · m (6.7 in. · lb)
- 4 mm hex key, 5.00 N · m (44.3 in. · lb)
- If necessary for easier access to the 3-Phase power distribution unit (PDU), open the rear door of the rack.
- Remove the right side panel of the ATE Core Configurations Generation 2 using the 3 mm hex key.
-
Unscrew the four screws to remove the 3-Phase
filter cover bracket from the 3-Phase PDU using
the T10 Torx head screwdriver.
- 3-Phase filter cover bracket
- Disconnect the 3-Phase filter input cables from the 3-Phase PDU using the T30 Torx head screwdriver.
-
Disconnect the DC contactor cable from the 3-Phase PDU.
- 3-Phase filter input cables
- DC contactor cable
- Unscrew the ground cable ring lug from the ATE Core Configurations Generation 2 using the #3 Phillips head screwdriver.
- Unscrew the four screws which mount the 3-Phase PDU to the front mounting rail brackets using the T10 Torx head screwdriver.
-
Unscrew the four screws that mount the rear side mount brackets of the 3-Phase PDU to the rear rails of the ATE Core Configurations
Generation 2 using the 1.70 N · m #2 Phillips head screwdriver.
- Ground cable ring lug
- Front mounting rail brackets
- Rear side mount brackets
- If necessary, unscrew the ground cable ring lugs from the contactor cover using the #3 Phillips head screwdriver.
-
Unscrew the four screws to remove the rear service panel using the T10 Torx
head screwdriver.
- Rear service panel
-
Unscrew the five screws to remove the contactor cover using the T8 Torx head
screwdriver.
- Contactor cover
- Disconnect the panel-to-contactor cables from the (3NO) contactor using the #2 Phillips head screwdriver.
- If necessary, disconnect the daisy chain contactor cables from the contactor using the #2 Phillips head screwdriver.
-
Disconnect the circuit-breaker-to-contactor
cables from the contactor using the 4 mm hex
key.
- Panel-to-contactor cables
- Daisy chain contactor cables
- Circuit-breaker-to-contactor cables
- Remove the contactor from the DIN rail.
- Install the new (3NO) contactor on the DIN rail.
- Reconnect the panel-to-contactor cables to the new contactor using the #2 Phillips head screwdriver.
- If necessary, connect the daisy chain contactor cables to the new contactor using the #2 Phillips head screwdriver.
- Connect the circuit-breaker-to-contactor cables to the new contactor using the 4 mm hex key.
- Screw in the contactor cover using the T8 Torx head screwdriver.
- Screw in the rear service panel using the T10 Torx head screwdriver.
- If necessary, screw in the ground cable ring lugs to the contactor cover using the #3 Phillips head screwdriver.
- Mount the rear side mount brackets of the 3-Phase PDU to the rear rails of the ATE Core Configurations Generation 2 using the #2 Phillips head screwdriver.
- Mount the 3-Phase PDU to the front mounting rail brackets of the ATE Core Configurations Generation 2 using the T10 Torx head screwdriver.
- Screw in the ground cable ring lug to the ATE Core Configurations Generation 2 using the #3 Phillips head screwdriver.
- Reconnect the DC contactor cable to the 3-Phase PDU.
- Reconnect the 3-Phase filter input cables to the 3-Phase PDU using the T30 Torx head screwdriver.
- Reinstall the 3-Phase filter cover bracket using the T10 Torx head screwdriver.
- Reinstall the right side panel of the ATE Core Configurations Generation 2 using the 3 mm hex key.
- If necessary, close the rear door of the ATE Core Configurations Generation 2.