Reverse Polarity

[pmoyne]

Need a sanity check, I have a customer issue... installed a customer supplied consumer unit as they had the supply brought into the basement, so 3 ciurcuits had to be extended etc tested it all issued certificates etc. all fine. however halfway through the day the customer asked when was i going to do the basement consumer unit. I said it wasn't agrred and i would not have enough time that day. however I agreed to move the meter tails as they would reach the new supply. I did this and did a direct ZS on the ring main and all checked ok.

They agreed to have me back in three weeks to do the basement consumer unit. the saturday night before going in on the Monday saying he didn't want me back, because his wife had a electric shock from the washing machine and had lost confidence, this was the 13th of march they then got and electrician on the 31st of March who said the meter tails had been reversed and this was horendous and had caused the electric shock.

Apart from various stories changing and they started off saying I have switch the live into the earth bar 1st, but have changed it to the polarity reverse, would this cause the plumbing to go live.

They are asking for money by the way...

any advice would be helpful.

 

[Notsosmart]

We asked a qualified (37 yrs experience) NICEIC registered electrician to investigate what had gone wrong with our system, and why Di had suffered an electrical shock. He found the fault within a few minutes, as the live and neutral tails coming into the basement consumer unit had been switched by you, at the end of the days work you did for us. You'll recall no doubt that you put the live power back into the old consumer unit after partially installing the new box, but as this was incomplete you put the tails back into the old unit - but critically you put them in the wrong way round. I can easily obtain written confirmation of this by the new registered electrician should you wish me to. He was shocked and appalled by your mistake, and was amazed that you hadn't performed any safety checks that could have quickly detected the problem, and averted the shock.

Feel for you Pmoyne

I would take them up on this offer first, before accusing them of trying to scam you and before you get anyone else involved.
If as others suspect this other electrician is in fact bogus you can easily check his NIC registration (make sure you ask for his NICEIC number to be included in the report)

BTW I once replaced tails to existing Henly blocks only to find that the meter fitter had put in his cables in reverse polarity ( I.e. black out of the meter) if I hadn't noticed & just connected like for like then I could have had the same situation, although polarity checks would have highlighted the issue.

 

[pushrod]

Just trying to get my head round this - not sure but am i right in thinking that rectifiers in appliances would be unaffected by a L - N reverse ? (just thinking about bridge rectifier? diode types.)

And if an earth fault developed (to the neutral) this would still trip an rcd but it would not stop the fault , but then wouldn't the main fuse then blow ?

 

[wattsup]

If poles were reversed, then snooker on telly would be fun...cos the balls would jump out of the bags..is the hoover blowing rather than sucking? is the fridge getting hot?...

 

[pushrod]

If poles were reversed, then snooker on telly would be fun...cos the balls would jump out of the bags..is the hoover blowing rather than sucking? is the fridge getting hot?...

that's what i was wondering about - depends on the type of motors involved though doesn't it? If they are dc motors through a rectified source they won't misbehave? but if they were ac ones they would go backwards or am i thinking about 3 phase with a wire out of place ?? nope it is too late at night for me - i should have paid more attention in the motor lectures - can't get my brain in gear

Mind the whole thing sounds very suspicious - why wouldn't the customer call the original electrician back straight away as soon as they thought something was wrong?

 

[martysparky]

The socket in reverse I found had an iron plugged in it and it didn't freeze the clothes.

Things would still work correctly except they would remain live even when the switch is open and the appliance appears off.

As far as I know not sure about motors either.

Did the washing machine make the clothes dirty. Maybe that was the shock.

 

[shane]

don't know abouut you guys but cheque the polarity before during and after installation of ccu or any circuit installed, the very first thing you do before energising the cu is wait for it"polirity"...

 

[martysparky]

check three times, once for each conductor.

Triple check!