What is the difference between instrument earthing and normal earthing? and why is it necessary to do so?

Answer Posted / mugil

Instrument Earth:
Instrument Earth is also called as Reference earth.Instrument Earth all individual shields(Screen) and
over all shields single or multi pair cable shall be isolated from electrical earthing due to avoiding interference and terminated different bus bar.
Instrument bus bar will be connected to grounding dispatcher by 25 sqmm green- yellow cable.Grounding dispatcher to earth pit is connected to 70 sqmm green -yellow cable.

Electrical Earth:
Electrical earthing also called as dirty earth or protective earth.It is used to protect the power system,electrical equipment and personnel from electric shock.

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