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URL of this page :
https://www.nwo-i.nl/en/personnel/working-conditions/working-with-electricity/how-do-i-disconnect-items-from-the-power-supply/

Printed on :
August 15th 2019
01:23:39

Low voltage (to 24 volts)
Disconnect the cable attached to the chassis.

Mains voltage (230/400 volts)
You can disconnect from the power supply by pulling the plug out, switching off the isolating switch or removing the safety fuses (and taking these with you). Always leave a warning behind that this part must remain disconnected due to work being performed.

High voltage

  • Alternating current: > 1000 V effectively between two phases or > 600 V between one phase and the earth
  • Direct current: > 1500 V between two poles or > 900 V between one of the poles and the earth

In the case of high voltage the work is always entrusted to a qualified person. The power supply is disconnected in the same way as for ‘mains power’. However, switching off a piece of equipment does not guarantee that there are no live parts. The qualified person will discharge live components by applying a clearly visible earthing with an earth stick.