Dead short between 3 conductors

[growler]

What reasons can anyone think of why a circuit would have a dead short across all 3 conductors ?
so far I'm thinking
- water damage
- possible rodent / pest damage
any more ?

 

[7029 dave]

Crushed or cut cable?

 

[Octopus]

water!

 

[HandySparks]

What reasons can anyone think of why a circuit would have a dead short across all 3 conductors ?
so far I'm thinking
- water damage
- possible rodent / pest damage
any more ?

If you really do mean 'dead short' then the only thing I can think of would be a couple of nails or screws driven into the cable and connecting adjacent conductors.

 

[jaypp]

if nothing altered/changed and no other works carried out (i.e. fault just manifested), I'd agree with water/rodent.
Recently a fault on lighting circuit with outside lights showing ingress of moisture (you could have kept a goldfish in it), simple I thought! Split conductors, s/w open all good, s/w closed, not! Also found a 'half severed' t&e feeding outside light. No work in vicinity for 13 years, when roof was replaced. Took that wet spell we had for it to be a problem (along with the o/s light)

 

[uksparks]

A house I went to the other day, a there was a leg coming off a socket going "somewhere" that appeared to hve a dead short across all three, disconnected and then everything was fine, no idea where it went though and everything still worked, it was a radial and house was empty so easy to check everything.

A mystery, but I got my money, rcd stayed in, I walked out the door.

 

[SirKit Breaker]

Impact damage, or just plain good old fashioned deterioration. Or has anyone had floorboards up etc. there is usually more to the tail than the customer will admit.

Cheers.............Howard

 

[Darkwood]

Everyone is taking shots in the dark here ...what was the IR results ...did you do a Ohms test and are you sure no loads were connected ...all it takes is a transformed AC/DC supply with noise filtering to mimic these results ... please elaborate on your situation.

 

[Guest112]

A house I went to the other day, a there was a leg coming off a socket going "somewhere" that appeared to hve a dead short across all three, disconnected and then everything was fine, no idea where it went though and everything still worked, it was a radial and house was empty so easy to check everything.

A mystery, but I got my money, rcd stayed in, I walked out the door.

Yeeeeeeeeeeeeeehaaaaaaaaaaaaaaaaaaaaa hahaha

 

[Silly Sausage]

Yeeeeeeeeeeeeeehaaaaaaaaaaaaaaaaaaaaa hahaha

If he chopped it back enough so it couldn't be re-connected and the customer's happy, sounds OK to me.
Why waste hours tracking down an irrelevant fault!

 

[Marvo]

...what was the IR results ...did you do a Ohms test and are you sure no loads were connected ...

My thoughts also. Are we talking about a dead short tested with a Mega tester at 500v or a dead short tested with a low-ohm meter. It would be better if you gave us an actual value and what test equipment was used.

 

[uksparks]

If he chopped it back enough so it couldn't be re-connected and the customer's happy, sounds OK to me.
Why waste hours tracking down an irrelevant fault!

Yes disconnected and put in 2 way wagos then wrapped in tape and put a label on it from the label machine, I have no idea where it went and everything still worked so was not planning on spending all day looking for something.

 

[PEG]

A common reason for a "dead short" across the three conductors,if that is indeed what has occurred,is a pulled or strained t&e through a bare steel aperture,for example a backbox or steel studding.....usually after the decorators have left...

 

[davesparks]

What did you join it to with the wagos?

 

[uksparks]

I'll be honest I just left them wrapped up at the back, cutting them off at the entry to the box will not help the next person. It was safe, I didn't just cut the ends and leave them, well not this time anyway, maybe next time...

 

[uksparks]

I just used two wy wagos just to cap the ends sorry, just one conductor in each.

 

[davesparks]

I don't see what advantage putting a wago on the end of it has?

If you want to make it safe then connect them all to earth

 

[se7aq]

If he chopped it back enough so it couldn't be re-connected and the customer's happy, sounds OK to me.
Why waste hours tracking down an irrelevant fault!

The house next door hasn't got power though..!

 

[JD6400]

I don't see what advantage putting a wago on the end of it has?

If you want to make it safe then connect them all to earth

I see where you are coming from , but personally if I were ever to leave a unknown cable without finding it's purpose .
I would do as uksparks has , this way it can be reconnected if found to be needed , and although banging down to earth is good practice for known circuits which are now obsolete , I would be very wary of doing so with one of unknown origin / destination .

 

[davesparks]

Well he knows the destination is a dead short L-N-E as that is what the thread was all about when it started.

 

[JD6400]

If you don't know what a circuit does or where it goes then how can you tell its origin or destination ?

 

[davesparks]

The cable originates at the point it has been disconnected, and it has been disconnected due to a dead short L-N-E.

 

[JD6400]

I know what you mean and would tend to agree with that , but what's to say it is not going to some form of micro generation ( PV / Wind ?) , against the regs granted ! But still possible .
Or it could even go out to a little generator which gets plugged in when the power is out . I have seen this on more than one occasion and the home owner just knocks the main switch off when the genny is plugged in .



Edit; Never underestimate the power of stupidity , and how a little knowledge can implement that stupidity !