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CSCS Health & Safety Test· CSCS / CITB

For portable electric tools on a UK construction site, the preferred safer supply is:

Choices

  • A230 V mains
  • B110 V reduced low voltage (yellow plug and transformer)Correct
  • C415 V three phase
  • DAny voltage available

Answer

110 V reduced low voltage (yellow plug and transformer)

110 V reduced low voltage, supplied through a centre-tapped transformer with yellow connectors, limits the shock voltage to around 55 V to earth, making it much safer than 230 V for site tools. Battery tools are safer still.

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