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Reply To: HV vs LV Contact Procedure

  • Graeme Johnson

    Member
    4 August 2021 at 5:58 pm

    Procedure for High Voltage / Low Voltage Clash

    1 Purpose

    This document outlines the procedures to apply when High Voltage and Low Voltage circuits have clashed.

    2 Instructions

    2.1 Identify the area affected by the clash and inform the Control Room so that the affected area remains isolated.

    2.2 Ensure that any Transformer(s) servicing the Low Voltage Network where the High Voltage /Low Voltage clash has occurred are isolated before any High Voltage lines are energised.

    2.3 Inform the Supervisor of the situation and make arrangements for an Electrical Inspector to attend and inspect All MEN installations associated within the Low Voltage Network where clash occurred.

    2.4 Isolate any installations that have damage prior to re-energising the Low Voltage Network. Isolate the Low Voltage from any transformer(s) effected where the clash occurred by removing the Low Voltages fuses (or where there are no fuses, remove the tails from the LV bushings, but leaving the neutral connected at all times)

    2.5 Advise the Control Room of you actions and gain permission to energise the transformer so testing can be conducted to ensure it is functioning normally. If satisfied with the test results then advise the Control Room you are ready to reliven the Low Voltage Network once inspections have been completed to ALL installations.

    2.6 When inspections have been completed, advise the Control Room and re-energise the isolated Low Voltage Network area. Advise the duty supervisor of any installations that have been isolated for safety. If no person is onsite, leave a card in the letterbox advising them their installation has been isolated for safety reasons, and to contact their local electrician.

    3 OUTCOME

    3.1 To ensure that no harm can come to any person or further damage to property resulting from a High Voltage / Low Voltage clash. Duty supervisor to be updated throughout the process and with an end result of which installations have been isolated for safety.