Does my office require RCBO's (hence new DB)

[browfish]

I have been told by my electrician that because RCBO's are not available for my existing distribution board in my office at work, i will need to install a new DB. Is this true? I have had conflicting advice.
The only circuits are
Lighting -run above suspended ceiling with switches chased into wall (existing before work but replaced fittings)
Power points on wall, again chase in but existing.
new power points run in mini trunking surface mounted

Do i need this or are they trying to sell me something i dont need. I know a new installation would have RCBO's but in a commercial building is it necessary?

Thanks

 

[JohnD]

what sort of DB do you have?

 

[browfish]

no idea sorry. It is about 20 way, and probably early 90's. Thats about all i can tell you

 

[londonboy]

Fit external RCD and enclosure for new sockets in minitrunking, and leave the rest as it is.

 

[browfish]

My contractor as taken the liberty of installing it because i need it and charged me £650 for a 16 way board.

So in your opinion this was not required? How much should the RCD option have cost as i may argue that i should only pay this amount.

thanks

 

[kevindgas]

robbing barsteward!! you should have phoned round and got estimates we would have charged 1/2 that!! unless it was really difficult then a bit more would have been added but i have never charged over £450


i wish i had customers that wanted to spend!!

 

[ericmark]

1) There is no requirement to upgrade unless you have done an alteration which now requires a RCD which would not have required one before.
2) If the work was to sink wires into the wall at less than 50mm then there are two methods.
a) Use cables designed for the job i.e. Ali-tube.
b) Use a RCD.
3) For existing sockets no need to fit RCD.

However most companies would want to ensure the safety of their workers and so would want to have RCD protection on sockets. There are two basic methods.

1) Use RCD sockets.
2) Use RCD in the distribution board.

Now cost can go either way and not easy to work out cheapest. At £50 for a double RCD socket plus the extra cost of Ali-tube cable by time you have fitted 12 sockets then spending £600 on a new distribution unit would be cheap option. At £25 for a RCBO a single phase 16 way board would cost £400 to populate and a three phase board £1200. And that's with cheapest RCBO in screwfix's catalogue and does not include price of box or fitting.

It is correct to say you don't need to change the board but it still could be a cheap option.

Prices of RCD devices do seem a little strange. £21.17 for a single socket and £8.05 for it built into a plug. Only real difference is socket is passive and plug active type. And Volex double RCD socket £21.10 and MK £50.08 from same supplier. So without seeing what is already installed and exact spec no one can really comment on price.

 

[Spark123]

Without seeing the job it isn't possible to say that you have been charged over the odds.

 

[cumbriahandyman]

Pictures...

 

[ban-all-sheds]

It is correct to say you don't need to change the board but it still could be a cheap option.

An RCD in a small enclosure would be cheaper still.

Even 2 or 3 RCDs, if there are that many circuits.

 

[londonboy]

robbing barsteward!! you should have phoned round and got estimates we would have charged 1/2 that!! unless it was really difficult then a bit more would have been added but i have never charged over £450


i wish i had customers that wanted to spend!!

I dont think its fair making this comment, this board is in a commercial environment and for all we know it could have been done out of hours.

There are too many variables.

 

[holmslaw]

..

 

[Paul_C]

Your electrician is incorrectly applying domestic requirements to a commercial premises. In commercial premises installed and maintained by competant staff there is no requirement to install RCD's or RCB's for standard internal circuits.

Precisely. Absolutely no requirement in BS7671 for RCD protection on all sockets in commercial premises.

 

[plugwash]

I thought they were required on all sockets intended for general use and below a certain current value (don't remember exactly what off the top of my head, think it's either 20A or 32A) regardless of domestic or commercial, am I wrong.

 

[Paul_C]

I thought they were required on all sockets intended for general use and below a certain current value (don't remember exactly what off the top of my head, think it's either 20A or 32A) regardless of domestic or commercial, am I wrong.

It's 20A and below in a domestic installation. There is no general requirement for such RCD protection in commercial premises where the outlets will be used by a "skilled or instructed person."

Outlets <=20A in non-domestic installations require RCD protection only if they will be used by "ordinary persons" (i.e. anyone who is neither "skilled" nor "instructed"), and even then there is an exemption for sockets intended for supplying specific equipment and so labeled.