more than one circuit

[Geffers]

HI people, doing a CU change for my assessment & there are a couple of circuits using the same mcb (for example a lighting circuit & an outside light wired into a 6a mcb) As the job does not cover me doing anything but the change & as there are no spareways on the cu is this going to go against me? should i put it on the EIC? or can i suggets we uprate the mcb? Any reply would be helpful.

:innocent

 

[ProDave]

Surely if it's a CU change, then you have fitted a new CU with insufficient circuits? Should have fitted a larger one. :coat

 

[NozSpark]

Generally this wouldn't be a problem, just because the joint is at the MCB doesn't make it 2 circuits...

However, to simplify things why not put them on different MCB's?? this is allowable on a CU change you know!

---------- Post Auto-Merged at 17:31 ---------- Previous post was made at 17:30 ----------

When changing a CU you should alwaye try and leave a couple of spare ways for future work

 

[Andy™]

a circuit is anything connected to an MCB. doesnt matter if it has 2 wires feeding off to 2x radials of whatever, its still 1 circuit

and what makes you think uprating the MCB will be any good? chances are, if you do, it will be above the max the cables can take, and you will definately get a non-compliance

 

[ADS]

.....for example a lighting circuit & an outside light wired into a 6a mcb)

Do you seriously think this is a problem, that it will go against you and requires mentioning on an EIC?? :|

 

[Geffers]

Thanks for the replies. a bigger cu is a no go due to space. however there a 2 x socket radial circuits also sharing the same mcb (which i assumed to be a ring) i will uprate them to 20amp but is it still acceptable? can i have 2 x radials on the same mcb?

 

[Andy™]

can i have 2 x radials on the same mcb?

i give up.

 

[Geffers]

Thanks everyone much appreciated replies

 

[safedepth]

Thanks for the replies. a bigger cu is a no go due to space. however there a 2 x socket radial circuits also sharing the same mcb (which i assumed to be a ring) i will uprate them to 20amp but is it still acceptable? can i have 2 x radials on the same mcb?

Geffers,

You need to listen to what's being written for you??? If you see what I mean.

Also, don't assume anything, test it. I refer to the 2 x socket radial circuits. What size CPD is on it now. If 32a you would be derating them. If it is a ring it can stay at 32a.

Test, test, test.

 

[Badger]

i dont mean to be funny but are you a diyer or a trade electrical contractor, as surely if the later your experience should be already known to you about this :C

 

[Megaohm7]

Did you do any test's before you changed the CU? This will help with identifying any other circuits. I've recently changed a board for my assessment and I discovered the kitchen extractor hood on it's own circuit? and the lighting circuit has two separate circuits going into the mcb?. As it was a bungalow It was easy for me to go up into the loft and sort out the lighting circuit so it tidies things up in the CU. It's all labelled up correctly too as it should be..

 

[Manator]

Geffers, if I was your assessor I would at this point be very concerned about your ability. First of all any CU change should only be carried out after initial testing and identification of connected circuits. Two legs of a lighting circuit are allowed into one CPD, providing the characteristics of protection allow this and ,as it can often be presumed as a spur is excepted.

Your assessor will ask you about this, you will have to give a confident reply. Regarding the question about radial or ring, this can only be confirmed by testing, again the results of these tests will be questioned by your assessor. Your answers to these questions will be the difference in passing the assessment or failing miserably.