New consumer unit -I think I've done a very simple 'stupid' - help please.

mikeymix · Aug 4, 2018

I've just swapped out an old consumer unit for a new one - like for like in terms of circuits.
One lighting circuit will not set.

I've disconnected the earth on that circuit and it still won't set so I would appear to have a live-nuteral short.

However I did nothing to that circuit at all during the change over.

I've tried connecting the circuit to a different Rcd it still won't set.

I have also examined the cable at the Unit to check it's not been damaged.

What 'stupid' might I have done?

telectrix · Aug 4, 2018

does it trip with the landing light on at switch or off?

Marvo · Aug 4, 2018

If you're replacing CU's I'm assuming you're a sparky.
What won't reset, MCB or Rcd?
Why would you disconnect the CPC?
Did you do any tests on the lighting cct? What were the results?

MJPD29 · Aug 4, 2018

Is it an mcb or rcd tripping? Is there a crossed neutral between the lighting circuits? Also, if your not an electrician are you sure this is work you should be undertaking and what are your means of testing it

Octopus · Aug 4, 2018

Test kit ? Certificate ? Competence ?

Taylortwocities · Aug 4, 2018

Murdoch said:
Test kit ? Certificate ? Competence ?

And notification!

Think we know the answers to this!

mattg4321 · Aug 4, 2018

westward10 · Aug 4, 2018

I've disconnected the earth for that circuit. Great idea, as above are you an electrician.

Wilko · Aug 4, 2018

Hi - I think you are going to need on site help with this.

stevethesparks · Aug 4, 2018

mikeymix said:
What 'stupid' might I have done?

Changing the CU whilst not being competent to do so.

Toneyz · Aug 4, 2018

What have you swapped the consumer unit from and to a photo might help to see if a cable is in the wrong terminal.

westward10 · Aug 4, 2018

I have a vision of a house in pieces.

JAWS · Aug 4, 2018

Without trying to sound rude I really hope you are an electrician becuase this aint even funny, any dangers could be shouting out if you didnt know what you were doing.

Toneyz · Aug 4, 2018

Massive1 said:
Without trying to sound rude I really hope you are an electrician becuase this aint even funny, any dangers could be shouting out if you didnt know what you were doing.

Well, you don't remove the earth and then liven up the circuit.

Pete999 · Aug 4, 2018

mikeymix said:
I've just swapped out an old consumer unit for a new one - like for like in terms of circuits.
One lighting circuit will not set.

I've disconnected the earth on that circuit and it still won't set so I would appear to have a live-nuteral short.

However I did nothing to that circuit at all during the change over.

I've tried connecting the circuit to a different Rcd it still won't set.

I have also examined the cable at the Unit to check it's not been damaged.

What 'stupid' might I have done?

Where are you situated Mate, someone close to you may be able to take a look.

Midwest · Aug 4, 2018

I think you've all been had.

Wilko · Aug 4, 2018

Midwest said:
I think you've all been had.

Admin can sort it if necessary

.

johnduffell · Aug 4, 2018

mikeymix said:
What 'stupid' might I have done?

forgotten to test? What test equipment have you used?
presumably the MCB tripping since you mention possible LN short.
have you removed all loads (bulbs) and disconnected L and N but not cpc and tested between each two of the three?
If you had done that you might know more.

There was a not so recent case of installers not doing any testing and "blowing" away the faults by turning on the MCB repeatedly. Then it had left in a dangerous state which later caused a fatality. So just think about what you are doing and whether you can test properly (not just carry on until the MCBs stay in)

Joshua · Aug 4, 2018

This guys name is almost Mickey Mouse, think we've been trolled.

telectrix · Aug 4, 2018

westward10 said:
I have a vision of a house in pieces.

buzzlightyear · Aug 4, 2018

mikeymix said:
I've just swapped out an old consumer unit for a new one - like for like in terms of circuits.
One lighting circuit will not set.

I've disconnected the earth on that circuit and it still won't set so I would appear to have a live-nuteral short.

However I did nothing to that circuit at all during the change over.

I've tried connecting the circuit to a different Rcd it still won't set.

I have also examined the cable at the Unit to check it's not been damaged.

What 'stupid' might I have done?

only you can answer that ,next .