Switchboard in a hazardous area

[victorgoh]

In Australia, we use TN-C-S system. I have a switchboard feeds a pump in hazardous area. I knew for switchboard in Hazardous area it needs to connect to a TN-S system. So should I remove the MEN link in the switchboard? Could anyone help me with this matter? Thanks.

 

[Baluncore]

Welcome to PF.

Maybe this will help understand or ask the question. Sixth page of pdf.
https://www.ee.iitb.ac.in/course/~emlab/assets/earthing.pdf

Why is the area hazardous? The definition and classification of “hazardous area” may have implications for fault currents to Earth.

PF cannot give legal advice, so you will need to consult your State Authority for their interpretation of the standard. It will be their peculiar interpretation that you must follow.

 

[Guineafowl]

In Australia, we use TN-C-S system. I have a switchboard feeds a pump in hazardous area. I knew for switchboard in Hazardous area it needs to connect to a TN-S system. So should I remove the MEN link in the switchboard? Could anyone help me with this matter? Thanks.

I’ll start this by saying if you don’t know, then get a professional installer in.

Are you sure you mean TN-S? That would mean installing an extra wire going back to the transformer. TT would be more likely.

The usual practice is to isolate the two earthing systems. The cable supplying the hazardous switchboard would have its Earth linked to the TNCS system at its origin, but isolated at the destination (plastic gland). That way, the TNCS protects the cable only.

At the switchboard, you would set up a TT Earth as if no TNCS existed, ie use only the live conductors from the cable.

 

[Guineafowl]

Any comments, OP? Always nice to tie up a thread.