Consumer Units/knockouts

[rugbyspark1]

Hi there folks,
Have been using BG boxes for years, now getting fed up with all these knockouts at wrong size for 3rd ed glands.
Have complained to BG but they dont reply, started back with MK but their just the same !. Have any of you complained to these Mfg to get their knockouts at the right size so we dont have to modify ?.
Also found the BG High Integ Units difficult to fit RCBO's, cable too short and mains bus too small for connections.

 

[littlespark]

It was so much easier using teeth on the plastic boards.

 

[Rpa07]

Judging by some of the photos on the thread ‘Dodgy Trade Pics’ I think some have been for quite a while!

It was so much easier using teeth on the plastic boards.

 

[Dave OCD]

Never mind all that palaver with glands, just mount the CU on a nice new backboard spaced off on small battens then bring everything in through the big rear knockout/s [Suitably grommeted of course].

 

[freddo]

There is one company selling consumer units that can be supplied without knockouts. Forget who though. I wish they all did that, the holes are either the wrong size or in the wrong place. I usually use my hydraulic punch set as it can do square holes too.

 

[Leesparkykent]

There is one company selling consumer units that can be supplied without knockouts. Forget who though. I wish they all did that, the holes are either the wrong size or in the wrong place. I usually use my hydraulic punch set as it can do square holes too.

Hager.

 

[Andy78]

Hager.

I think they are going to start offering circular knockouts too, think I read somewhere lately.

 

[ipf]

Never mind all that palaver with glands, just mount the CU on a nice new backboard spaced off on small battens then bring everything in through the big rear knockout/s [Suitably grommeted of course].

Why grommet?.....just cut a smooth hole in the ply....smaller than the metal cut out.

 

[Dave OCD]

Well yes I've done that but thought I'd get some grief on here if I said it.

 

[Gavin John Hyde]

one of the better CU's is the Curve range in Denmans/Rexel has lots of space in top for rcbos, quite affordable too. you can get one with 6 rcbos for 89+vat, extra rcbos only £13. not had any failures yet. my preference is Hager but sometimes customer wont pay for it, so been using the curve range. has nice square knockouts and glands for it, or you can use rear or round glands

 

[multimick]

curve are good loads of space above, but just fitted 3 contactum DEFENDER boards they are very solid and well made ,they are now my first choice

 

[Nobbin]

Never mind all that palaver with glands, just mount the CU on a nice new backboard spaced off on small battens then bring everything in through the big rear knockout/s [Suitably grommeted of course].

I do this for most of my CU's.
I like the BG kit, they provide a nice plastic trim for the rectangular knock-out in the back. Saves my file for another day.
For the time it takes to resize holes and screw in glands I've cut and mounted the CU on 4 battens, knocked out the back hole/s and already started terminating.
I am an advocate of the 'trunking for tidiness' clan. I think it looks neater than glands and you get a lot more "wiggle room" to work with while hiding away those nasty cables.

 

[rugbyspark1]

Tails glands are nothing to do with the third amendment, they are not required by it.

Strange that, regs say your supposed to keep the fire integrity of the unit !. Therefore all glands should be of the the Fireproof variety !. Also the back hole needs the same firproofing. Ring mains 2 x 2.5 glands use 25mm holes most knockouts are 20mm. YES I use Wiska variety not the cat type, just in case anyone is smart enough to ask.

 

[Electric Magic]

Strange that, regs say your supposed to keep the fire integrity of the unit !. Therefore all glands should be of the the Fireproof variety !. Also the back hole needs the same firproofing. Ring mains 2 x 2.5 glands use 25mm holes most knockouts are 20mm. YES I use Wiska variety not the cat type, just in case anyone is smart enough to ask.

Bullocks. 421.1.201 doesn't say that. In fact, Richard Townsend from the IET said the following in response to a frequently asked question on the subject:

Question: When I put cables into a new metal consumer unit, do I have to use intumescent glands to enforce the fire protection of the consumer unit?

IET Response: No, the metal consumer unit is designed to encase a fire within it and restrict the likelihood that a fire may spread. Manufactures’ have carried out exhaustive tests on this issue and have found that the cable entry does not have to continue the fire rating of the consumer unit, for it to be effective. The only requirement is to keep IPXXD or IP4X on the horizontal surfaces (Reg 416.2.1) and IPXXB or IP2X on all other surfaces (Reg 416.2.2). Intumescent glands and sealants may be used to ensure the IP ratings are maintained, but they are not a requirement and existing methods of ensuring IP are acceptable.

 

[Andy78]

Strange that, regs say your supposed to keep the fire integrity of the unit !. Therefore all glands should be of the the Fireproof variety !. Also the back hole needs the same firproofing. Ring mains 2 x 2.5 glands use 25mm holes most knockouts are 20mm. YES I use Wiska variety not the cat type, just in case anyone is smart enough to ask.

The regs don't say anything like that at all. They require the board case to be of a non combustible material, that's it.

Making a 20mm hole into a 25mm hole is your problem here ? Really ?

 

[Midwest]

A thread on how to make holes, I am glued to this.

Your getting confused, that's a thread about mounting back boxes in old bricks or something