What are the causes of a L N short on a ring

[easysushi]

Gents

What are the causes of a live/neutral short on a ring?

Appliance still pluged in , damaged cable etc


Cheers

T

 

[Deleted member 9648]

Pretty rare...most faults are L-E or N-E....Low L-N Ir readings are nearly always the result of a load still on the circuit somewhere.

 

[easysushi]

when doing continuity test on L and N I get continuity ?


Have check sockets ect can't find where its coming from


T

 

[Deleted member 9648]

Do you mean you are doing a continuity test between L-N ???.....Is the MCB blowing ?....whats the story?

 

[ezzzekiel]

nail through cable etc

 

[easysushi]

Do you mean you are doing a continuity test between L-N ???.....Is the MCB blowing ?....whats the story?

Spured of a ring circuit, doing r1+r1 , r2+r2, rn+rn end to end test. Also noticed that I was getting r1 and rn continuity. MCb not blowing, I is at a loss as to what it could be.


T

 

[ezzzekiel]

not sure on the question, if you have a dead short between line neutral then the mcb is gonna pop.

im guessing you are looking at something plugged into the circuit

 

[Hawk81]

a neon in a spur will give you those readings

 

[pushrod]

If you are insulation resistance testing between L and N then a neon in a socket will give the impression of a short or you have something still switched on - spur to central heating control or boiler via an FCU is a common one.

 

[easysushi]

Not doing IR just continuity. Everything is unpluged that I can find, a lamp or somthing still plugged in, would that give me continuity

 

[Hawk81]

yes it would

 

[easysushi]

funny cos my megger mft does pick fault up breifly, but my kewtech voltage meter has constant tone

Any idea#s

 

[Amp David]

Is it a circuit you have wired or one you're just testing?

 

[alarm man]

any alarms spur'd off the circuit sometimes without a fcu,alarm psu transformers can read around the 1 to 2 ohm mark when metered

 

[easysushi]

Is it a circuit you have wired or one you're just testing?

Just testing the circuit,