Changing size of Neutral Terminal Blocks in a Consumer Unit

[Chris Osborne]

Hi all! I'm rewiring my house at the moment and I have a consumer unit and some RCDs, MCBs lying around, the consumer unit is standard but I want to turn it into a split load, 

my question is - is it safe to cut down (saw) the neutral terminal blocks at the top so they are shorter? because at the moment the 3 neutrals I have plus the earth bar = too long to fit across the top of the unit! 

Any experience here would be helpful, I'v looked around to see if I can just buy smaller terminal blocks but can't seem to find any!

Cheers, 

Chris

 

[Andy™]

depends if you want to take full responsibility for modifying the board to relevant british standards and then certify it as being safe or not...

easiest and safest option would be to stop being tight and go buy a new one designed for the job

 

[Evans Electric]

Yes you can .  BUT you will need some extra plastic posts that hold each end of the bars   .

Although different makes look the same ..they don't fit .

I'm guessing the board has a line of square holes across the top and your, at the moment , has an earth bar & a Neutral  so you need two extra plastic doo-dahs to form three separate N bars .

What make is the board?  

Ask at the wholesalers if they have a board thats been broken or raided for parts .

( There is a load stuff these days about altering the manufacturer's specification ....It wouldn't bother me to be honest , in fact they'd never know by looking at your altered board)

Edit :-   I wrote the last bit before Andy's reply ...its up to you ...I did it myself last week on a Wylex  which was a split load fitted by council .....one RCD  with everything on it and  6 blanks in the other half .   At least its now a proper split .

 

[Andy™]

I'm guessing the board has a line of square holes across the top and your, at the moment , has an earth bar & a Neutral  so you need two extra plastic doo-dahs to form three separate N bars .

its most likely a plastic CU, so unless its in a bombproof cabinet or was designed prior to amd3 then it wont comply with current regs

 

[Evans Electric]

Yes but if it's  already there we're not obliged to replace them all are we .....or are we ?      We just don't fit them anymore.

I'm going back this week to a project we did  two years ago  to alter some stuff   ,  I won't be replacing the board for metal . 

 

[Blue Duck]

Ask your local wholesaler if they have a box of spares behind the counter?

 

[Andy™]

Yes but if it's  already there we're not obliged to replace them all are we .....or are we ?      We just don't fit them anymore.

I'm going back this week to a project we did  two years ago  to alter some stuff   ,  I won't be replacing the board for metal . 

not a very good re-wire if your re-using old parts that you have lying around

 

[Chris Osborne]

Thanks, It's actually a BG metal CU and complys with Amd 3, I do have the extra plastic "doo dahs" and I have the 3 neutral bars, but as I say the neutral bars, as they are, are too long and I don't need so many seperate neutral connections in each terminal block. 

The only thing that crossed my mind is if there was a maximum load on the design of the terminal bar and by cutting it shorter it presented a risk of over heating but that could be me being over cautious.

 

[Lurch]

not a very good re-wire if your re-using old parts that you have lying around

Doesn't sound anything wrong with that. You saying you only use parts you get over the counter from the wholesaler and you always check that the dates are in the last month or 2?

 

[Murdoch]

Maybe buy a bunch of RCBO's - much better than dual RCD units.....

 

[Evans Electric]

Thanks, It's actually a BG metal CU and complys with Amd 3, I do have the extra plastic "doo dahs" and I have the 3 neutral bars, but as I say the neutral bars, as they are, are too long and I don't need so many seperate neutral connections in each terminal block. 

The only thing that crossed my mind is if there was a maximum load on the design of the terminal bar and by cutting it shorter it presented a risk of over heating but that could be me being over cautious.

Chris , its not a problem , just cut them off & crack on with it .    You'll need some some extra flexible L & N  cable links too. 

One day we'll all be dead and those neutral bars will still be there ...and no one will ever know that you cut an inch off one end.

Maybe buy a bunch of RCBO's - much better than dual RCD units.....

They are but don't always fit well into standard boards .    Horses for courses. 

 

[binky]

if you cut a busbar, you probably improve its load carrying capacity - think about it, less holes means less circuits....in theory :^O

 

[Chris Osborne]

not a very good re-wire if your re-using old parts that you have lying around

Andy, thanks for your input but I never said I was using old parts - All the parts are new / unused within the past month or so, theyr'e just spares I have from other jobs

Chris , its not a problem , just cut them off & crack on with it .    You'll need some some extra flexible L & N  cable links too. 

One day we'll all be dead and those neutral bars will still be there ...and no one will ever know that you cut an inch off one end.

They are but don't always fit well into standard boards .    Horses for courses. 

Thanks Evans, I'll have a go at that then! 

 

[Murdoch]

Why would you cobble together a botched CU for your own house? A 10 way RCBO, AMD3 board can be had for about £140.00

 

[Lurch]

Why would you cobble together a botched CU for your own house?

My house has 2 cobbled together Vynckier/GE boards from 15 odd years ago. It is the way it is done, you do your own house in a "electricians house" sort of way. Same way that a plumbers house has leaky taps and temp pies strung up outside for no apparent reason.