Earth and cable monitor for earth connection failure

For electrical safety it is required to have earth wires connected to the transformer star point in any low voltage (eg 400 V/ 525 V) reticulation system. Earth leakage or protection relays rely on a healthy earth connection because they operate on the current in the earth wire. With a broken earth connection they are worthless. The earth connection can fail due to various causes, including cable theft. When it fails it is tantamount to an electrocution waiting to happen. A recently developed earth and cable monitor (ECM) could be the answer to earth connection failure.


Take note

  • A compromised earth continuity conductor is a safety hazard.
  • Earth continuity conductors must be continuously checked for integrity.
  • The earth and cable monitor (ECM) is an electronic device that will monitor and report a compromised earth continuity conductor.


Published as:

Monitor resistance of earth wire and improve safety

By E Häussermann, Mercutech; and J Warwick, Jojen Supplies

Electricity+Control, February 2013 (pages 8 – 9)

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