Changing an MCB after socket extension

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Merry Christmas everyone.

Earlier in the year we had some plastering and I took it as an opportunity to extend the ring circuit to our bootroom. That was 2 sockets plus a lighting on a 16amp mcb.

It was my intention to get an electrician in to change the mcb and while I'm happy wiring sockets, I have yet to venture into a consumer unit (which is where things shall stay!).

Over the last few days, we switched the gas aga on for cooking and noticed the mcb tripping for the pantry / bootroom. We had no trouble over the summer and the only variable is the aga. But it's not electrical, although the cu is directly above. I wondered if there was something to do with the heat from the aga although think might be coincidence. When I checked the cu I remembered the 16amp mcb.

So I expect this needs upgrading. We have 12 sockets on this plus a single light. I used 2.5mm cable to extend the ring and it doesn't extend to anything near 50m.

We have a TV, a large american style fridge freezer and assorted lamps and a laptop on this circuit. I suspect the content opening and closing of the fridge, plus the added Xmas lights might now be overloading the breaker.

Q1: Is a 20amp mcb enough for this ring? I've read conflicting info.
Q2: Would it be prudent for rcd to be fitted?

Our house has about 5 cu that have all been doing different things over the years so unravelling the mess from the previous owners is something not really complete. Most recent certified work on this cu was the fitting of an additional rcd for the ev, just to the left of shot. This is fed by that ev breaker in shot.

Before I post the job, I was after some clarity on the above. Many thanks!
 

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Oh and to add, the master cu where the feed comes in does have rcd protected circuits.

Do you mean the submain to the board pictured is RCD protected?, or just simply that another board which is located at the orgin (and may or may not supply this one) has a number of RCD protected circuits? Even if the former, it may not be good, if the RCD turns out to be an AC type, given that an EVSE has been hung off the board you pictured

I think you'd be best having an EICR (Electrical Installation Condition Report) carried out to establish what sort of condition things are in and go on from there depending on what the outcome is.
 
Hi @Adam_151. I double checked and it is not the former. My mistake. I just triggered the main switch and board pictured is still live. We have had Western Power come and upgrade the main fuse as a result of our ev install.

We have certificates for the majority of works that have been done in the house, and have had new CUs fitted elsewhere so we're happy with how things are at the moment (apart from this immediate problem).
 
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Merry Christmas everyone.

Earlier in the year we had some plastering and I took it as an opportunity to extend the ring circuit to our bootroom. That was 2 sockets plus a lighting on a 16amp mcb.

It was my intention to get an electrician in to change the mcb and while I'm happy wiring sockets, I have yet to venture into a consumer unit (which is where things shall stay!).

Over the last few days, we switched the gas aga on for cooking and noticed the mcb tripping for the pantry / bootroom. We had no trouble over the summer and the only variable is the aga. But it's not electrical, although the cu is directly above. I wondered if there was something to do with the heat from the aga although think might be coincidence. When I checked the cu I remembered the 16amp mcb.

So I expect this needs upgrading. We have 12 sockets on this plus a single light. I used 2.5mm cable to extend the ring and it doesn't extend to anything near 50m.

We have a TV, a large american style fridge freezer and assorted lamps and a laptop on this circuit. I suspect the content opening and closing of the fridge, plus the added Xmas lights might now be overloading the breaker.

Q1: Is a 20amp mcb enough for this ring? I've read conflicting info.
Q2: Would it be prudent for rcd to be fitted?

Our house has about 5 cu that have all been doing different things over the years so unravelling the mess from the previous owners is something not really complete. Most recent certified work on this cu was the fitting of an additional rcd for the ev, just to the left of shot. This is fed by that ev breaker in shot.

Before I post the job, I was after some clarity on the above. Many thanks!
Was the original 16amp circuit a RING in the first place?

And since you extended it (but reluctant to look in the consumer unit), was it made into a RING then?

Is it possible this circuit began as a RADIAL, and since your additions, still is a RADIAL?
 
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Q1: Is a 20amp mcb enough for this ring? I've read conflicting info.
Depends what you mean.

Whether 20A will be enough for the appliances used, it depends what you plug in.

Whether 20A is enough for a ring circuit, I would say not really.
The whole point of ring circuits is to have 32A with 2.5mm².
With a 20A MCB, or 16A as you also mention, there is no point having a ring circuit.
 
Was the original 16amp circuit a RING in the first place?

And since you extended it (but reluctant to look in the consumer unit), was it made into a RING then?

Is it possible this circuit began as a RADIAL, and since your additions, still is a RADIAL?
It is still a radial. I went back to my original sketches and remembered the plan was to extend a ring from elsewhere but it wasn't doable. The existing cable was a single one out of the cu, and I added two junction boxes to extend out and return back in.

I just pulled some floor boards and can confirm it.
 
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I've re-traced the circuit and think this might be running a little long (might even exceed 50m). I'm going to get someone in to look at it as I wonder if I should really be powering these sockets off their own MCB.

Having said all of that, just switched the Aga back on and it tripped within 30 mins. Confusing....
 
Sounds like you are overloading the circuit or the MCB is knackered

And that CU needs a professional look over too
 

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