Borrowed Neutrals ! (gotta be careful)

[muzza1]

Hi Lads, how are you all? Was just wondering if any you have come across "the hidden killer" (borrowed neutrals)? Thought it would be a good idea just to raise awareness. Thanx.

 

[Estimator]

Borrowed Neutrals, they're always treated as a bit of a joke....
I knew a spark who got killed by one in a commercial setting around 20 years ago...
From what I can remember he was working on a lighting circuit in a false ceiling, he'd tested everything was isolated and started work. Unfortunately, he touched the neutral after he disconnected it... That was it he was DEAD.
The HSE were never really convinced that he had tested everything... They didn't get that he completed the circuit...
This sticks in my mind as he was about the same age as me...
Killed because some idle spark saved an hour or two, by not installing one wire...

 

[Darkwood]

I got similar to borrowed N lesson in a unexpected way... was taking some Galv trunking lid off and as i pulled it away from the trunking i got a belt of the lid.... turned out after scratching my head that a socket neutral had come out of a connector and rested on the lid which gave a return path and i come along and get a right belt... although not a borrowed N it does highlight the dangers... i now always pull lid off from one end first looking behing as i do..... now they dont teach you these senerio's but just one of those things.

 

[KoFi]

Came across this recently 70w CDM-T fittings wired in multicore SWA 5 core 2.5mm TP&N Dis board time clock controlling contactors core 1=L1 ,2=L2 ,3=L3 ,4=N ,5= CPC. Armoured went into unit unknown location then re appeared in a 230v rated fitting where joints were made the three phases being linked (in singles) out so that every other two fittings were on a different phase via the contactors sharing the one neutral. one fitting had 400v across phase conductor and neutral break some where. not good practice.

 

[Leshark]

I just did a CU change, and found the hall upstairs pendant taking its live from downstairs & neutral from the upstairs circuit, being wired this way in the 70's with no RCD its likely it would not have reared its head, luckily, I could rewire without too much disruption

 

[Darkwood]

N break over 3ph systems can create floating star points giving voltages up to 400v across single phase points L/N.... common situe should be avoided in design of final circuits, hard to avoid if incomming N is lost because of gypo's nicking su station E/N tap.

 

[SolarSparky]

thanks

 

[KoFi]

I just did a CU change, and found the hall upstairs pendant taking its live from downstairs & neutral from the upstairs circuit, being wired this way in the 70's with no RCD its likely it would not have reared its head, luckily, I could rewire without too much disruption

seen this exact scenario this afternoon ! was a common finding on the landing light!
good practice always prove phase conductors dead (includes neutral)

 

[Essexboy7]

was doing a CU change last year and board was in a little cupboard under the stairs so i was all doubled up.The wiring in the house was an absolute mess,it had 2 extensions added over the years at seperate times and both times the wiring had been done by builders.So any way i was trying to trace a few circuits and do some fault finding and BANG i got a belt off a neutral.It blew me back across this little cupboard and i banged my head.My mate watching me said i was lying on the floor semi conscious groaning.Very scary experience which i NEVER want to repeat

 

[Silly Sausage]

That's why Neutrals are classified as Live conductors!
Glad your OK EB7

 

[Essexboy7]

I havent had a belt off a neutral for years and it was he first couple of milliseconds when i realized clear as day what was happening and i knew what was coming in the next instant!However that fear was quickly followed by the reality of being smashed onto the floor and lieing there in a mess.


The moral of the story is i had been there for a few hours and was geting frustrated and was rushing.It was a saturday and i fully expected to be away by 1 o'clock but this was about 3 0'clock and i hadnt even started to change the board.The more i tested the house and started taking things apart the more problems i was finding and i was worried about running out of daylight.So it was a good lesson to myself.Work in a safe manner at all times.Electricity does not respect age or experience it will kill you quite happily no matter who you are.As Archy Styrigg says That's why Neutrals are classified as Live conductors!

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[Sparks1962]

To true, Darkwood. I can't remember covering this in college. Even if it makes just one youngun stop and think before he chops (and grabs) it's well worth chatting about. Just reiterating the need to stop and think, only for a minute. could well save a nasty shock.

The subject of borrowed, pinched or stolen Neutrals ( depending on where you come from!) was one of the first things I was taught as an Apprentice, and drummed into me by the man I worked with, a flat capped, bib-and-brace overalled, collar and tie wearing Sparks of the old school. Brilliant chap who had probably forgotten more than I've learned lol!

I hope they still stress this important subject at college now ??

 

[shanky887614]

The subject of borrowed, pinched or stolen Neutrals ( depending on where you come from!) was one of the first things I was taught as an Apprentice, and drummed into me by the man I worked with, a flat capped, bib-and-brace overalled, collar and tie wearing Sparks of the old school. Brilliant chap who had probably forgotten more than I've learned lol!

I hope they still stress this important subject at college now ??

nope.

they don't mention anything about that.

 

[Sparks1962]

Do they leave it to the employer then? Apprentices should learn this stuff from day one !

 

[shanky887614]

Do they leave it to the employer then? Apprentices should learn this stuff from day one !

my employer has never spoken to the college i went to.


they teach whats in the exam and thats it, usually there are bits in exams they missed off

 

[stuartcourt]

really is lethal