can anyone can give detail how to do cable tray earthing in hazardeous area ,can we connect to electrical pit ,since there is no instrumentation earthing pit
Have a look at the earthing information detailed in your applicable hazardous area standard.
You will need to give more information if you want a better answer (along with the applicable hazardous area standards you are trying to comply with, zones, dust/gas, etc).
Earth is earth is earth. There is nothing special about equipotential bonding in hazardous areas.
If it were not in a hazardous area, how would it be done?
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