104 MaintenanceAfter the DC link capacitors have discharged completely, the cabinet doors of thepower compartments unlock, the SUPPLY OFF pushbutton changes to a permanentlight and the status line displays .4. Rack-out, lock-out, ground and tag-out the main power feeder.5. Switch off and lock-out all auxiliary voltages from external sources.6. Verify that the drive system is de-energized.7. To connect a grounding set, continue with Connecting a grounding set on page 104.8. To open the door of the medium voltage compartment, continue with Unlocking andlocking the doors on page 104.Tip: To open the power compartment doors, auxiliary voltage is required.9. Before start working in the power compartment, the power modules must beindividually grounded by touching them with the grounding stick. See Groundingpower module with grounding hook on page 107. Unlocking and locking the doorsThe door is secured by a safety switch and the control compartment door has pivoted doorhandles and locks with triangular inserts. Open the door with the supplied key.1. To release the door handle, insert and turn the key to the right. The door handle willpop out.2. To open the door, turn the door handle• to the right, if the door is hinged on the right,• to the left, if the door is hinged on the left.3. To lock the door, bring the door handle in line with the door plate and press the handledown until it clicks in. Connecting a grounding setBefore starting to work on the drive, you must ground the three input and three outputterminals in the terminal unit (TEU). Always ground the drive on both sides, i.e. on supplyand motor side. Grounding on motor side is needed to avoid induced voltage from aspinning rotor.
