Which consumer unit and RCBOs?

[TTbangbang]

:x

got it! Strange how something can be staring at you right in the face but you have to look at it from another angle in order to see it!

Thanks. So metalclad CUs ok for TTs provided a double pole RCD, in an all-insulated enclosure, is upstream. The things the OSG doesn't say X(

Thanks again, will sleep tonight :z

 

[davetheglitz]

I know of absolutely no reason why you can't use metal CU on any system, as long as the casing is suitable earthed, its suitable for the environment etc etc.Grommeting holes is simple good practice on any metal enclosure.[/quote

Concur with Binky (God bless Terry Pratchett!)

Metal enlcosure - providing bonding and earthing is in place - no problem. All metalwork at same potential in case of a fault.

Once had a bit of a belt off a metal CU which wasn't earthed (fed from a plastic CU - but no earth stapped across - L-E fault downstream) Always a bit suspicious when I see that arrangement nowadays!

 

[davetheglitz]

Think I replied to page 1 of this thread! However the arguement still stands - if all is earthed and bonded there shouldn't be a problem even if the main fuse doesn't blow! All metalwork at same potential. Big question is do you trust the theory and is everything bonded??? Wonder how this works out as a risk assessment in our health and safety conscious society? Might be best to use an insulated CU or insulated RCD before as suggested!!

 

[kme]

OK.

r.e rcbo type. I`ve now started using "hager". Contractum are way too tight in the board, wylex are, erm, dunno `cos I can never get the buggers. MK are like rocking horse poo, and crabtree want too much dosh!

r.e. m/c versus plastic on TT. I have also seen the note in the OSG. I must admit to having a dislike of metalclad units in a TT installation. Steptoe`s approach may well be ok, but it isn`t a practice I would personally consider. RCD front end, even S type, is not what I would be specifying, from a design POV, either

 

[TTbangbang]

Thanks for that, it's good to have POVs from the experienced.

Hager CU and RCBOs it is. I personally would go for a double pole time delayed RCD at the front, as the RCBOs will be single poles. To toe the OSG line, I will go for a plastic CU.

Thanks again everybody

 

[steptoe]

Thanks for that, it's good to have POVs from the experienced.Hager CU and RCBOs it is. I personally would go for a double pole time delayed RCD at the front, as the RCBOs will be single poles. To toe the OSG line, I will go for a plastic CU.

Thanks again everybody

are you going to RCBO every circuit? you will have to going this way to meet BS7671.

wouldnt it be better/cheaper to have a split board? dual RCD and seperate main switch for your RCBO'd ways.

just a thought.

 

[TTbangbang]

are you going to RCBO every circuit? you will have to going this way to meet BS7671.wouldnt it be better/cheaper to have a split board? dual RCD and seperate main switch for your RCBO'd ways.

just a thought.

Yes, I was planning to RCBO every circuit, it's the simplest and most up to date option...as well as being the most expensive :_| .

 

[green-hornet]

For a domestic installation complying with the 17th Edition where all the final circuits are RCD-protected, an RCD main switch is no longer required, provided that the consumer unit is of all insulated construction.

This means a metal CU would not be acceptable without a time delayed rcd main switch

 

[Andy™]

This means a metal CU would not be acceptable without a time delayed rcd main switch

er....

not quite. for TT it would need to be insulated, unless there was an RCD before the CU

for TN, there will be a nice big earth path for any fault current to open the . like someone drilling through a SWA with with no RCD

unless ive missed something....

 

[Apache]

Spose it also depends on which wholesalers / retail outlets have the greatest clout the get the supplies from MK when they are available?? ?:| On a lighter note...

its good news for Spam lovers..

Tescos, Sainsbury's & Occado home delivery can do a 340g tin for

 

[sanny]

[No message]