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AllAspects

Hi, just starting out on my own having gained C&G qualifications and first job has been to replace a friends jumble of old fuse boxes into a nice new 17th edition CU. All going fine, circuits transferred over yet when I energised the unit none of the circuits on RCD1 worked. I moved some of them over to RCD2 & they were OK. I then put only a short busbar on RCD2 & this is OK as well. Is there a limitation on the number of circuits I can have on RCD1 ?
Cheers
 
So what testing did you do to determine why the circuits on RCD1 weren't working?
What was the supply voltage between the input terminals to RCD1?
With RCD1 switched on, what was the voltage between the output terminals?
 
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Just re-read the OP and realised that you're saying that RCD1 works OK supplying fewer circuits. No, there's no set limit, although you need to take the loading on each RCD into account when designing the installation.

Sounds you're doing fault finding by just swapping things round until they work. You're not going to learn much from your faults that way.
 
On the face of it, this situation can't happen, reducing total number of circuits on RCD1 then allows the remainder to suddenly start working??

There's some information missing or the connections to the RCD's are loose.

First, Photos of the board and connections would be good and a photo of the test gear you are using.

The next popular request you're going to get is to be asked for the test results for all the circuits before you changed over.
 
Maybe you could post a photo of the board (without the cover on).

How did all the dead test results look?
 
Either u haven't tightend the busbar on the circuits that ain't working or some of the MCBS are faulty on that rcd. Are the Mcbs new? I agree with snow head, pictures please :)
 
Isn't that what the OP is saying by the RCD's/circuits worked and didn't work? It's a bit difficult to work much out from 1 short post with very little detail.
 
He's got his words mixed up I think. Read his situation, apparently rcd1 has never worked lol. None of the circuits on rcd1 worked so he moved them to rcd 2 and then they worked. He then shortend the busbar on RCD2 and it worked but I think he means he shortend them on rcd1 then it worked which would be impossible unless he means the rcd is tripping so he removed some circuits (shortening the busbar) removing the circuits that have the neutrals in the wrong place perhaps? This would make sense but he didn't say the rcd trips
 
I must confess I was wondering why he'd moved the busbar, that bit didn't make sense either.
 
Some original posts assume everyone is a mind reader and or is standing in front of the problem.

However to the O.P, if you come back;

Is RCD1 tripping?
Is RCD2 tripping?

With no circuits connected and mains onto the incomer of the RCDs, is there a voltage reading on the outgoing side of Rcd 1 and RCD2, if so what reading?

If the RCDS are tripping with circuits connected and you don't have any test gear, connect each circuit 1 at a time and power up till you find which circuits are tripping.

However if this is your first job and it's for assessment for a scam, you've failed without test gear and for not using any prior to changeover.
 
aaaaAAAAAaaahhhhh! See? I took it that some circuits were causing the RCD to trip (doesn't really matter if it's 1 or 2) and by moving some ov the circuits over to the other RCD they held. Still, until the OP comes back with the rest of the info, I'm outa here.
 
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I am going to be very blunt with this reply

The very simple action of testing the rcd,or the circuits associated. given the apparent unusual function of his set up,leads me to believe that either there is something very basically wrong with his construction of the board,there have been no test instruments used, or if there are test instruments,the person needs to obtain an understanding of how to use them

The situation described should not become problem enough to warrant looking for advise
 
Rather pointless thread this one. Its a simple matter of testing for voltage at the top of each MCB then the bottom, then the buzzbar, then the RCD top and bottom and seeing where it starts/stops. The fact that the OP hasn't worked this out for himself would suggest to me he really hasn't got the slightest clue what he is doing and Im suprised he's recieved so much advise.
 

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Wylex dual rcd 15 way consumer unit
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AllAspects,
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