Apprentice needs help three plate wiring

[jjrules2]

I've wired in some lights from scratch. Unfortunately when I turn on the 6A MCB with the light switches in the "On" position, the MCB trips. When the lights switches are off, it doesn't trip, as soon as they are turned on, trip!

I wired one 1.5mm cable from the CCU to the first light. Brown in middle feeds part of pendant, Blue in neutral part of pendant, Earth to earth (feed in). Second Cable out of first pendant in same connections as above, brown to feeds, blue to neutrals, earth to earth for "feed out". Last cable down to the light switch, where I took the brown to the feed connector block to take 230v to the switch and I put the blue in the "live" part of the pendant and sleeved it brown. Earth to earth.

What have I done wrong here? Thought I was getting this but I am now just confused. Or do I have faulty switches? They are 1G switches. Brown in common, blue in L1.

Sorry if this is so easy for some of you but I am still learning and feel very stupid that I don't know the solution! Thanks

 

[gavin.sibley]

I had exactly the same problem last week, I would check first that you haven't caught one of the cores in the switch with the facia screws... Failing that possibly a knackered switch

 

[Lou7]

Where does the second cable go ?

 

[jjrules2]

the second cable goes to another pendant. So have my feed in cable, feed out cable and switch cable. But as soon as I turn it on, it trips! Have 3 brown wires connected together, two blues and one Blue sleeved as brown for the switch live! Don't know what's gone wrong.

Both switches trip the RCD though? What does this mean?

 

[jjrules2]

This is exactly what I have done!

 

[jamesBoater]

So whats actually tripping the MCB or RCD? if RCD then check the neutral in the board? is the board split loaded?

 

[jjrules2]

RCD is tripping sorry not the MCB.

Neutral in the board looks fine. IR'd the circuit and all fine and clear? Confused.com

- - - Updated - - -

Board is split loaded with cooker and ring circuit on this side of RCD. All working fine, issue just with this one lighting cct

 

[mtfpuk2011]

cheaxl the main earthing termal and have connected them in the the same squints as the brakera and natural

 

[dave992]

Fault lies on the switch side so double check where your blue ( sleeved brown) goes and also the next pendent or check all pendent, could be a simple mistake that everyone make or you might have clipped a cable or something down that line.

 

[jamesBoater]

So is there 2 RCD,S ? if so check the neutral for you lights is in the right neutral bar for the rcd its on?

 

[Phoenix]

Is the neutral on this circuit connected to the correct Neutral bar in the CU?

 

[Richard Burns]

You probably have the neutral cable in the CU connected to the wrong neutral bar, (if it is a split load CU)

 

[jjrules2]

OK I will check the neutral bars in the morning. It is a split loaded board

Lights, cooker, ring kitchen on one side

Smokes, Ring, boiler on other.

Is there a way I can IR the switch line to see if a screw has gone through it?

 

[D Skelton]

Apologies in advance if my assumption is wrong but where were your dead tests before energising? These would have brought any of these issues to light. I know you're only learning hence my soft reply but this is fundamental to being a safe and professional electrician. I would suggest that in future you get the test gear out before the fuse goes in!

If you're 100% sure your wiring is correct I'd put money on one of your patress screws chewing through a live conductor. I'd also check your neutral is in the correct bar in the DB.

Edit: beaten to it

 

[bartkusal]

I've wired in some lights from scratch. Unfortunately when I turn on the 6A MCB with the light switches in the "On" position, the MCB trips. When the lights switches are off, it doesn't trip, as soon as they are turned on, trip!

I wired one 1.5mm cable from the CCU to the first light. Brown in middle feeds part of pendant, Blue in neutral part of pendant, Earth to earth (feed in). Second Cable out of first pendant in same connections as above, brown to feeds, blue to neutrals, earth to earth for "feed out". Last cable down to the light switch, where I took the brown to the feed connector block to take 230v to the switch and I put the blue in the "live" part of the pendant and sleeved it brown. Earth to earth.

What have I done wrong here? Thought I was getting this but I am now just confused. Or do I have faulty switches? They are 1G switches. Brown in common, blue in L1.

Sorry if this is so easy for some of you but I am still learning and feel very stupid that I don't know the solution! Thanks

It may sound stupid, but where did you terminate your earth in the switch? Hope not in L2, seen that done, and when switch is operated it will trip.

 

[Octopus]

OK I will check the neutral bars in the morning. It is a split loaded board

Lights, cooker, ring kitchen on one side

Smokes, Ring, boiler on other.

Is there a way I can IR the switch line to see if a screw has gone through it?

Did you not do that before you energised the circuit?

What does your mentor say?

 

[v.elec]

Correct inspection and testing procedures prior to energising the circuit would mean that this fault would have been detected beforehand, therefore no protective device would be tripping out. Surely dead testing has been performed before switching the power on.

 

[SirKit Breaker]

You are an Apprentice, so i wont question your methods etc, as you are still learning. But what i will question is the ability of your Instructor, he should have let you wire up as the diagram, and checked it looking for faults. He should then have told you it is either OK or not, and if not, he should have got you to look it over to see if you could spot the error/s visually, and if you couldn't he should have helped you. If all was OK he should have gone through the correct test regime, and then finally energise and live test the circuit. These are basic's that you should be getting help with. Have you been taught Safe Isolation, Lock off tag off?

Cheers...........and keep asking,

Howard

 

[ackbarthestar]

A long time ago we fired in some T&E for a kitchen ring turned it on, without any tests as we thought our work was beyond reproach, and the RCD tripped out.
Eventually got the tester out of the van and checked the IR of each leg and found that the cable neutral had migrated through the insulation and was in contact with the cpc. Bloody annoying !
I know it has only happened to me once in 30 years. How many of you check the cable before chopping it up into pieces ?

 

[Nicky23]

Wiring using 3 plate makes life difficult at the fitting unless it is a ceiling rose, far easier if there is only 1 cable to terminate, I wire every light back individually to either a switch or jb, chopping a deep box it only takes a few extra minutes.
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