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Electrical Isolation
Electrical isolation refers to the process of safely isolating circuits or equipment from electrical power sources in such a way that circuits cannot be inadvertently re-energised or equipment restarted. It should not be confused with galvanic isolation in transformers or to prevent corrosion.

Safety standards require that, before working on them, electrical circuits and systems are:

•	 de-energised and isolated, •	 the isolation secured against being unintentionally re-energised, then •	 tested for voltage. Opening a switch or circuit breaker does not provide a safe isolation unless it can be locked in the open position and a second lockable isolation point is also obtained. The second isolation point provides greater integrity in case a switch is faulty. Any capacitors need to be discharged and prevented from being recharged during an electrical isolation. While switches or circuit breakers may be energised until they are opened, isolators are not. Circuits or equipment are not safely isolated until they have been tested for voltage.

Isolation and International Standards
Australian and International safety standards for mining and extractive industries require two independent and verified points of isolation (or discharge) of energy sources for drives of fixed plant, such as a conveyor. All points of isolation need to be secured by locks with informative tags and require a manual process to re-energise an isolated circuit when work is completed.

Remote electrical isolation systems
Remote isolation systems use automation and control processes to conduct and verify electrical isolations remotely from the location of the points of isolation. The operator of equipment in the field can use a safety-rated remote isolation system to rack-out safety contactors without the need for an electrician to attend the related switchroom or substation. To be safety-rated, it must be fault-tolerant, fail-safe and include self-diagnostics. Remote isolation devices also require lockout/tag out functionality and to be manually reset to re-energise circuits or equipment.