Racking System And Disconnect - ABB SafeGear Installation, Operation And Maintenance Manual

8. Racking System and Disconnect

A racking system is integral to the controller. Racking is only possible with the door closed. The racking system has two positions (Connected and Test /
Disconnected). In the connected position both primary and secondary contacts shall be engaged. In the test/disconnected position, primary contacts are separated
from the bus contacts while the secondary contacts remain engaged to the controller to be tested.
Interlocks
The truck has three different mechanical interlocks in the controller construction:
1. 1 The first makes it impossible to rack the controller in with the door open. (Highlighted in green).
1. 2 The second interlock does not allow opening of the door with the controller in connected position. (Highlighted in green).
1. The third and last interlock mechanism, is a padlock upon the principal screw (worm gear) to prevent racking when the controller is in connected or
3
disconnected position. (Highlighted in green).
SafeGear Motor Control Center Controller Installation, Operation and Maintenance Manual 6
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