I was looking inside my Hager CU today and noticed that two of the MCBs have their positive terminals linked by a purpose-made copper link made of pressed sheet copper (covered by a removable white plastic insulator. Additional MCBs, added more recently, for subsequent circuits are linked by short lengths of 10 sq mm cable with red insulation. Is this OK, or should all the MCBs be linked in the same way?
Thank you.
Axel
It might be OK, but can you post a pointer to a photo?
You have a DC supply to the house?
The copper "comb" is the one provided by the manufacturer for commoning the line input to the MCB. Usually every MCB is fed from the same comb.
It seems as if someone didn't have access to the original installation kit or couldn't be bothered to buy the part, and has simply used what was to hand when wiring in extra MCBs. AFAIK it's not a problem, it's just not as neat as using the correct part.
All MCBs will not be on the same bar if it is a split load type. All modern consumer units are split load type. Some are fed from the main switch and some from the RCD. There shouldn't be any problem if it's working. You can buy the appropriate piece of copper bar for a few pounds from electrical wholesalers. 10mm cable will take the 45A required for some showers for example. Put the lower rated MCBs at the end of the chain if you see what I mean.
Beg to differ but all consumer units are not split.
Have something to add? Share your thoughts — no account required.
Ask the community — no account required