Reverse Polarity

[housewife59]

Apologies for intruding on your website - I am NOT an electician!! I would like some advice - a couple of weeks ago a MeterPlus employee came to fit a new meter in my house - he spotted a fault - said it was reverse polarity - the whole house was affected & told me to get an electrician to sort the problem. To cut a long story sort the problem was identified yesterday as aNEDL problem arising from underground cabling in the village 5 years ago. Basically I was told that the tails to the box on the outside of my house had been wrongly connected causing the reverse polarity. I would like to know what if any risks this has posed to me & my family over the last 5 years but more worryingly if the instalation was wrong to my property what about the rest of the village? Any comments or observations would be most welcome

 

[rocker]

basically, wherever you have a switch to turn off an appliance or whatever, the electricity should come in through the wire to the switch, then therough the appliance, and when you turn off the switch the electricity comes down the wire and stops at the switch. When you have rev. polarity, the elctricity comes into the appliance, all the way through the appliance and then stops at the switch - what you think is not live will be live. If you were to perform maintenance on anything i.e. changing an internal fuse when the device is just switched off (no completely unplugged, which really it should be) the part you are working on could be live, if you touch it the electricity could find a path to earth through you and you could recieve a shock.

As far as the rest of your village - contact your local authority. They may contract some lucky electrician to check the whole village for polarity. On the other hand, they may just ignore you, depending on who your local autority are.

 

[Sintra]

Surely this issue should have been found on initial verification of the installation. Unless the DNO changed their supply after this.

 

[rocker]

Yep it should have, leading us to the conclusion that:
-It was never carried out
-Any spark who has been in there since has not been doing his job properly.

 

[acat]

I think to put it n very basic terms for you a normal supply the red/brown cable is the live one and has all the switchs and controls on that cable. The black/blue cable is the return path and when you switch something off the black/blue should be dead and totally safe to touch.

With reverse polarity the black/blue becomes live and then constitutes a danger plus you will find that if you are using an appliance that is polarity dependant it would go backwards.

Hope that helps to explain it better to you


Chris

 

[housewife59]

We have not had ANY electrical work done in the property since NEDL did the underground cabling work 5 years ago - NEDLyesterday identified the fault as being in the tails to the box that was fitted on our house wall during the u/g cabling work
remember you are speaking to a novice here! what does DNO mean?

 

[acat]

District Network Operator or EDL in your case sorry about the slang


Chris

 

[housewife59]

Thanks for your reply - can you tell me what appliances would be polarity dependent?

 

[Sintra]

Everything in a normal domestic set up. Sockets lights etc.

 

[acat]

Very few in the domestic side of things and it would depend on who made it and how. If you were suffering from that sort of thing then you would notice for instance the hoover would be blowing instead of sucking.

What I would suggest if you are concerned at all let us know what your closest town is (not your address) and perhaps one of the forum members can come round and explain everything to you and put your mind at ease.


Chris

 

[ezzzekiel]

on a pme system this would also result in all metalwork (if bonded correctly) to rise to mains potential within the property.

 

[housewife59]

PME? novice speak please!! my family laughed at me when I said I got mini electric shocks from the water flowing from the taps when standing barefoot in my utility room - is this just me being electric or reverse polarity in action? also on a few occasions I have noticed a dull flicker from a fluorescent light when it was not switched on

 

[rocker]

Yep that is very possible, in laymans terms your neutral somewhere along the line is connected to your earth. In some methods of bringing the electricity into your house, this join is in the house itself (I'm guessing your electricity supply will be this type if it's five years old)
For a seperate reason, your water and gas pipes should be connected to earth, so if the power is coming in from the neutral rather than the line, then the earth should be live too, which would explain an unpleasant buzzing sensation from and metal pipes and water coming out of the pipes. This could potentially be very dangerous in fact fatal under the right conditions.

 

[mogga]

As Acat says if you give an approximite are you are in there may be onr of the forum member avaiable to put your mind at rest regarding things as they will have the qualifications and could speak to the DNO on your behalf and get things sorted

Please dont try and test things yourself Even get the local spark in Good luck

 

[acat]

If you are getting shocks from pipes etc please do not touch them and always ensure that your hands are dry and you have somthing on your feet that will insulate you. I woud suggest that you get an electrician to check your place out as soon as posible.


Chris

 

[rocker]

Sorry just to add - have your suplier sorted this out yet? I was under the impression they had. This needs to be sorted out immediately if it hasn't been already.

 

[housewife59]

Thanks for all your replies - websites like this are brilliant! If you ( all of you have been kind enough to reply to me) read my initial posting NEDL resolved the problem yesterday. My mind is at rest now but I am furious that a negligent NEDL engineer has apparently put my family at risk to a potentially hazardous situation for the past five years!! If we had not had a request from the meter reader to meterplus to install a new meter we would have been none the wiser of the danger that we were in, I am the type of person who gets shocks off baby buggies, supermarket trolleys etc my family just laugh at me so the mini shocks from the taps were just regarded as 'mum being electric'!! Am I supercharged because of my house?!?!

 

[housewife59]

I should have added this in my last posting - I contacted NEDLs customer complaints dept last night - I would have assumed that they would view a situation like this as a priority - lunchtime now & no reply or comment from them yet - I am rather disappointed, to say the least, in their lack of communication!! As I said in original posting - if my house was connected wrongly during the underground cabling job how many others in the village are at risk too!

 

[acat]

So long as you are safe now that is the mai thing next step is put your complaint in writing and if it is not resolved to your satisfaction the next step is the electricity regulator and the press.

On behalf of all the forum members wish you well


Chris

 

[pushrod]

. If you were suffering from that sort of thing then you would notice for instance the hoover would be blowing instead of sucking.

I've seen this written by a few people on here as a symptom of reversed polarity and thought that it was wrong for most motors, particularly anything running on rectified AC. Anyway just reversed the polarity on my vacuum and it still sucked

And lights are not polarity dependent for functioning ( For safety yes)

(tin hat on )

TBH it doesn't surprise me at all that a reverse polarity can go undetected for such a long time as isn't it only in fault conditions that it would become apparent and then it would be extremely serious as protective devices, eg MCBs, would not operate.