ABB PCS6000 Lockout Procedure

Question 1

Explain the procedure to lockout and access the Converter.

Answer 1

1. Isolate on the Generator Side of the Converter.
   Lockout Generator - Apply rotor lock, and screw in pin interlocks on rotor pins.
   Close both GDM (Generator Disconnection Module) disconnector to earth.
   Access Neutral Boxes to test and confirm there is no voltage present within Generator.
2. Isolate on the Grid Side of the Converter.
   Open Q01 Circuit Breaker on the GIS to disconnect from Grid and verify that the breaker is in the open position via the switch indicator.
   Confirm zero voltage via the VDS (Voltage Detection System) on the LCC (Local Control Cabinet).
   Close Circuit Breaker Q81 to earth to earth the 66 kV Main Transformer.
3. Isolate the DC-Link pre-charging module in the CCU (Converter Control Unit).
   Switch off breaker Q321 and lock-out.
4. Establish DC-Link grounding on CCA1 (Converter Cabinet 1).
   Switch the DC-Link Isolator on CCA1 to earth the DC-Link.
5. Establish DC-Link grounding on CCA2 (Converter Cabinet 2).
   Switch the DC-Link Isolator on CCA2 to earth the DC-Link.