RCBOs replacing MCBs

[kerching]

If doubling up clears the poblem tyennyou need to ascertain which is easiest to do.
Correct circuit feed to switch OR correct circuit neutral to the fitting

 

[Murdoch]

Wonder which mug will be signing off the EIC, Part P and the EICR?

 

[binky]

Done that but its not what we had previous, Id like to keep as was.

So needs rewiring correctly, which probably means holes in walls and redecorating afterwards.

 

[SPECIAL LOCATION]

What you had previously was one part of the circuit, (neutral conductor), being supplied by two sources of power MCB's
This is dangerous and does not comply with wiring regulations as every circuit must be completely independent of every other circuit..

Imagine a scenario with two ends of a ring circuit connected to different MCB lives...
it would have 'worked' in the old board.. but not with RCBO's as quite rightly the RCBO's can detect the danger that MCB cannot.

You either need some rewiring of the lights.. or just keep them as one circuit.
This really should have been picked up during the testing before connecting the RCBO's and making the circuits live.

 

[Fleeting]

Yes, doubling up clears problem.

Then the circuits have interconnected neutral conductors.

 

[Murdoch]

Then the circuits have interconnected neutral conductors.

1 x OCPD = 1 circuit

 

[Fleeting]

1 x OCPD = 1 circuit

It is two final circuits in my opinion but lets not go there, we will agree to differ.

 

[Andy™]

Done that but its not what we had previous, Id like to keep as was.

borrowed neutral then. either fix it prperly (run a new cable to either downstairs switch or upstairs light) and keep them as 2 circuits, or take the lazy option and make them 1 circuit, which arguably isn't compliant due to not being split up to minimise inconvenience incase of fault

 

[Joeski1953]

What you had previously was one part of the circuit, (neutral conductor), being supplied by two sources of power MCB's
This is dangerous and does not comply with wiring regulations as every circuit must be completely independent of every other circuit..

Imagine a scenario with two ends of a ring circuit connected to different MCB lives...
it would have 'worked' in the old board.. but not with RCBO's as quite rightly the RCBO's can detect the danger that MCB cannot.

You either need some rewiring of the lights.. or just keep them as one circuit.
This really should have been picked up during the testing before connecting the RCBO's and making the circuits live.

borrowed neutral then. either fix it prperly (run a new cable to either downstairs switch or upstairs light) and keep them as 2 circuits, or take the lazy option and make them 1 circuit, which arguably isn't compliant due to not being split up to minimise inconvenience incase of fault

I accept that Andy thanks.

 

[Joeski1953]

I accept that Andy thanks I also agree about compliance, but unfortunately I've been told MANY have done it, due to the fact it is!

 

[Fleeting]

Get whoever installed it back.

 

[NozSpark]

The easiest way to sort this is to stick them in the same RCBO (as already discussed)
If you really want them as 2 separate circuits then you’ll need to replace the strapper between the landing and hallway light switch as well as the switch wires from the landing switch to the light (as well as getting a permanent live to it all)

 

[SPECIAL LOCATION]

The easiest way to sort this is to stick them in the same RCBO (as already discussed)
If you really want them as 2 separate circuits then you’ll need to replace the strapper between the landing and hallway light switch as well as the switch wires from the landing switch to the light (as well as getting a permanent live to it all)

Not necessarily....

Sometimes you can get round it by just running a new neutral feed from the CU to the upstairs lights..
And split the landing off from the rest of the upstairs lights..

So downstairs circuit includes the landing light..
Upstairs circuit is everything upstairs excluding the landing light..

Generally easier to pull cables through on properties that still have a traditional airing cupboard on the landing or in bathroom..

 

[Andy™]

wireless switch downstairs and a perm live from another light upstairs through the loft would also work

 

[Joeski1953]

Thanks to all for advice, acting on it. Cheers.

 

[john clark01]

Thanks for that, firstly I'm not sure of type that was supplied with the unit, will check when I go back tomorrow, secondly I'm not sure of landlords rules and regs ( But will find out) coupled to that my brothers going off what the letting agents told him? If your right then i,ll pass all that on, I,ll certainly look into it.

Crikey don't believe a word of what letting agents say. They haven't got a clue.

 

[john clark01]

Newbie here, joe just joined thanks in advance.
Cutting a long story short, My brother has a property he's renting out, current certification advised plastic consumer unit needed changing, changed to metal with RCBOs and anti-surge. It will need a retest obviously, has anybody ever come cross led (internal controls and drivers) tripping the RCBO? All other fittings (with no internal controls) work, There is upstairs and downstairs and sockets all on separate RCBOs, I know I've heard about spiked inrushes etc, but what's the remedy? The fitting is very extravagant with bars that light up ( leds 4 long shaped bars) When this gets disconnected nothing trips. If that goes back up all lights upstairs will work, but when we switch this one on it trips? Has anybody come across this before, i will post a picture of fitting and control ballast if it helps, he wants it (being very expensive) back up.
Obviously we will need a retest but we cant do this until we have something on the landing. Previously the unit was plastic with mcbs, nothing ever tripped, it was certificated as he let it previously. He is acting on the advisory.
I'm just wondering if I'm, wrong with my speculation, and what to do next.
Thanks to all in advance, (go easy I'm new)

I have come across a failed led g9 lamp tripping a circuit. When the faulty lamp was removed the circuit was clear.

 

[Murdoch]

I have come across a failed led g9 lamp tripping a circuit. When the faulty lamp was removed the circuit was clear.

Likewise - I've come across quite a few "blown" LED lights that have created dead shorts too.

 

[Geoff1946]

LED lamps can easily go short circuit. Some have a bridge rectifier at their input, which obviously only needs one diode to fail to present a short circuit. Other types have a capacitor, where again a single fail is potentially a short across the supply. If these lamps contain any protection at all it will be a tiny fuse which may take longer to open than an MCB.

 

[SPECIAL LOCATION]

These are the internal driver part of a GU10 LED that took out a 6a MCB..
Elderly customer who couldn't get the lamp out of the fitting was was unable turn on the lights in that room until I could call round the following day.

There are plenty of bits that can fail inside LED lights!