ABB UniGear Digital, Commissioning And Testing Manual

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PANEL INTERNAL INTER LO CKING APPAR ATUS CO NTRO L TESTING
42 1VLG5000 17 C
5.1.3 Earthing switch
The earthing switch can only be closed if the circuit breaker is in the test position or
the plug is out.
The dedicated protection function for supervision of the earthing operation is ESSXWI or
ESSXSWI.
Relay control access to the shutter of the earthing switch shaft by means of blocking coil RL3.
Figure 60: Blocking conditions of the earthing switch in PCM600
Step 1/7
Move the circuit breaker into the test position and keep it open. Check the circuit breaker sta-
tus on the protection relay LHMI.
Figure 61: Single line diagram, the circuit breaker is open and in the test position
Step 2/7
Move the circuit breaker truck out of the test position about a half turn of the crank. Check
the circuit breaker truck status on the protection relay LHMI.
Figure 62: Single line diagram, the circuit breaker is in the intermediate position