100Ma Rcd main switch On TPN board

[hasel5]

Got a quick question for you

Been to a dilapidation job today and have the following

TNS-C 100A supply in a Build from 2008 with a 12 way TPN board

Main switch is A 100A 100 MA 4 pole RCD

No 30 MA RCD protection to any outgoing circuits.

So if any circuit has a earth fault whole board goes out lol

Thinking as coding as a C3 on the report

Any thoughts

Regards Nick

 

[westward10]

Have you enquired as to whether it suffers nuisance tripping. I probably wouldn't Code it at all.

 

[hasel5]

Empty building Installation is as base build so no tripping

 

[westward10]

Would fault protection to all circuits comply without it, take it away you will lose the protection it offers. I would comment that additional 30ma protection isn't provided where it may be required or that there is no division of circuits but generally I would not comment on the latter

 

[Deleted member 26818]

Is there a requirement for 30mA RCD protection on any of the circuits?

 

[hasel5]

Thinking 2008 being start of 17th so maybe cables buried in walls with no earthed metallic protection is a possible Plus socket outlets ?

 

[telectrix]

what's the earthing system? if it's TT that may be a reason for the 100mA RCD.

 

[Perci]

The 100mA RCD could be for fire protection, say if the building was to be used as a grain store

 

[hasel5]

Earthing system is PME and its a office block

 

[Perci]

An office block probably shouldn't have a 100mA main switch fitted as disruption of power can be a big problem for servers etc. I would just put it as a comment of the installation as its not against any regs so couldn't really see it being a code 3

 

[hasel5]

Thats my thinking as well just seems a strange idea to me

 

[sheppertonspark]

Would the 100mA RCD minimise disruption in the event of a single fault ? I don't think you could argue that it did so "requires improvement", C3.