Ground floor lighting trips out mcb

[Biggy]

Hi everyone,

My first post but straight in with a couple of issues.

I'll start with a 6amp MCB that keeps tripping out relating to ground floor lights.
For your info:

There is 10 x 3w led recessed lights in Kitchen, 8 x 3w led recessed lights ,plus a main central Led light (approx 100watt equivalent ) in the room next to the kitchen and then the same amount of lights and Main central light in the Back room. I would say the combined wattage including two outside lights (40watt each) will be around 480w so let's call it 500watt on the ground floor.

From my understanding a 60w bulb draws around 0.5amp so in effect 30 of the 60w bulbs (around 1800watt combined ) would require a 15amp breaker which would be comfortable, so based on this theory is the 6amp MCB actually overload on 500watts on Ground floor and this tripping the breaker .

The breaker does not trip immediately as can take 5-10mins sometimes longer, and in some instances it has tripped even when ground floor lights have been OFF.

The joist spaces have all been insulated with rockwool if this makes any difference as I want to eliminate any possibility before I start questioning my electrician who advises that maybe I should fit a 15amp breaker in as he feels 6amp is less power for 30 odd lights .

Can anyone shed LIGHT on this

I'll come to the second issue after I can get a solution to this.

Sorry for the lengthy explanation but I know there's nothing more frustrating than not arming knowledgeable people will full info and expecting solutions. Hope I've not missed anything out.

Hope to get a few responses and guidance as I have basic understanding of electrics.

Thanks

 

[Toneyz]

And this is a workshop, so yore starter for 10 is, which one is correct?

I see that's what you modelled your garage on.

 

[Rpa07]

They didn’t even check their spelling of ‘Building’ before they posted to the World on YouTube!

I see that's what you modelled your garage on.

 

[telectrix]

wrong pete. it should read your, not you're.

 

[Pete999]

wrong pete. it should read your, not you're.

Correct!

 

[Biggy]

Little update, I got family member who knows a little on electrics to come give a view on it whilst I'm waiting and he has tried the following:

Moved the live wire from the breaker to the one next to it which was a 16amp breaker and lights stayed on for an hour or so without tripping so didn't want to stay there waiting as it could have been hours before it tripped, anyway then moved wire back to its original breaker and it tripped after 10 mins.

Next thing he did was swop upstairs 6amp breaker to downstairs and see if upstairs trips to eliminate faulty breaker. The lights this time stayed on for 1hr 40 mins before I decided to switch them off and go home.
Returned this morning to find the trip had switched for ground floor, so this has definitely eliminated a faulty breaker which isn't the case.

He will check all switches for loose wiring today and maybe disconnect all led spotlights and just leave the two main central lights in each room wired up and then see if they trip, as he thinks if they don't trip then the problem may well be with the cheap transformers and may have to replace all transformers with maybe 5watt capacity to sufficiently supply the 3w led lights .

Only baffling thing is they can still trip whilst lights are off so somebody here mentioned it rules out the drivers .

As for the installer whether he is NIC approved , the answer is I am not sure but is there a way to check online or somewhere , I know the tester is as he provided the certificate .

 

[Markyd]

The 'TESTER' .......should not have tested and signed off the other persons work

 

[Biggy]

Seems to be common thing apparently round my end where sparky gets someone else in to certify it so is this actual illegal to do and why is it that they are qualified to wire up but not certify ? Is it just as simple as not having done the course to be a certifier hence why they use someone else to do it ?

 

[Markyd]

How do you know he is qualified to do the wiring....you said you didn't know if he was qualified at all......Have you done this job yourself and got a mate to sign it off without proper testing......if so your on your own

 

[Markyd]

And in the brown stuff up to your neck along with your mate​

 

[Silly Sausage]

this is a workship.
View attachment 46794

That's Boaty McBoatface, i'n't it?

 

[Octopus]

Seems to be common thing apparently round my end where sparky gets someone else in to certify it so is this actual illegal to do and why is it that they are qualified to wire up but not certify ? Is it just as simple as not having done the course to be a certifier hence why they use someone else to do it ?

If the person investigating the issues is unable or unwilling to provide a certificate, it would suggest that they are out of their comfort zone and you should be using somebody who is willing. ....... to do the whole job properly

I can't speak for your area, but if I get calls to ask me to sign off a another persons work - I decline to get involved.......... its that simple.

 

[Toneyz]

This fault is a bit of a hard one to solve from afar. You have now ruled out the MCB being faulty. Has an insulation resistance test been done by your mate and an RCD test? if both these tests are fine there must be an L-N fault somewhere.

 

[Harry_P]

This fault is a bit of a hard one to solve from afar. You have now ruled out the MCB being faulty. Has an insulation resistance test been done by your mate and an RCD test? if both these tests are fine there must be an L-N fault somewhere.

A simple insulation resistance test will identify exactly what the problem is and also where the problem is. Just changing the breakers around is not going to actually get you to the solution and any genuine electrician would do insulation resistance test before doing anything else
Ps if there is L/N problem the insulation resistance test will show you what it is and you can then trace the faults location(s) if you have the correct test equipment and you know how to use the test equipment and how to interpret the results

 

[Octopus]

A simple insulation resistance test will identify exactly what the problem is and also where the problem is. Just changing the breakers around is not going to actually get you to the solution and any genuine electrician would do insulation resistance armrest before doing anything else

Not sure I agree with that .................

????

 

[Harry_P]

Not sure I agree with that .................

????

Hahaha predictive strikes again
I have edited now