High ESB usage ... wiring question

bothyhead

Our recent ESB bill was high (310 eur), which came from approx 1,500 units used over a 68 day period. I know that we have a wiring problem, and wonder if that could be the cause?

For some unknown reason, our Neultral is not at zero, which results in the potential difference between N and L being significantly less than 220V. To bring the N back to zero, one of the sockets in the kitchen has a link wire between N and E. This set up has been like this for years, since about 1978 when a utility room extension was built.

We have always had ESB bills that seem higher than average (compared to friends). Could earthing the N at the socket be a contributing factor to our high unit usage?

Thanks

p.s. I have an electrician booked to come and investigate

M cebee

there shouldn't be any N-E links in the house


the link sounds like diy neutralizing

maxfresh

This sounds dodgy alright the only N to earth link is done at the esb cutout, maybe get the electrician to check the incoming voltage to see if that is at 230v

bothyhead

Yeah, it's dodgy alright. I only discovered it recently when I went to replace the socket. Hopefully the electrician can get to the bottom of it relatively easily.

What I'm really trying to find out though is if this is a potential leak as far as units are concerned. Our units used seem to be twice that of anyone else I've asked.

bothyhead

maxfresh wrote: »

This sounds dodgy alright the only N to earth link is done at the esb cutout, maybe get the electrician to check the incoming voltage to see if that is at 230v

I will do, thanks.

maxfresh

well if the voltage is decreased the current drawn will in turn increase

example 2kw element at 230v = 8.7 amps

2kw element at 200v = 10 amps

bothyhead

The link is permenantly in place so the voltage is always at a 'constant' value. Right now it's 223V.

It would be interesting to see what it's at if I temporarly removed the link. I might do that tomorrow in daylight.

M cebee

maxfresh wrote: »

well if the voltage is decreased the current drawn will in turn increase

example 2kw element at 230v = 8.7 amps

2kw element at 200v = 10 amps

no it doesnt work like that

M cebee

bothyhead wrote: »

The link is permenantly in place so the voltage is always at a 'constant' value. Right now it's 223V.

It would be interesting to see what it's at if I temporarly removed the link. I might do that tomorrow in daylight.

not a good idea

Bruthal

maxfresh wrote: »

well if the voltage is decreased the current drawn will in turn increase

example 2kw element at 230v = 8.7 amps

2kw element at 200v = 10 amps

You really believe this?

Well get a 2kw kettle, and connect to a 110v traffo. It will now be working at 500 watts, not 2kw.

All you have to do is get your grip ameter to prove it.

We have been down this fixed power appliances route not too long ago here.

maxfresh

my mistake

Bruthal

maxfresh wrote: »

my mistake

The 230v 2kw = 8.7 amps and the 200v 2kw = 10 amps would have to be 2 different elements designed to be 2kw at their respective voltages.

The first being 26.5 ohms, and the second being 20 ohms.

Bruthal

bothyhead wrote: »

Our recent ESB bill was high (310 eur), which came from approx 1,500 units used over a 68 day period. I know that we have a wiring problem, and wonder if that could be the cause?

For some unknown reason, our Neultral is not at zero, which results in the potential difference between N and L being significantly less than 220V. To bring the N back to zero, one of the sockets in the kitchen has a link wire between N and E. This set up has been like this for years, since about 1978 when a utility room extension was built.

We have always had ESB bills that seem higher than average (compared to friends). Could earthing the N at the socket be a contributing factor to our high unit usage?

Thanks

p.s. I have an electrician booked to come and investigate

If this link did fix a voltage problem, that would indicate a problem neutral, esoecially if the installation is already neutralised at the meter.

An installation with a sound neutral wont have any voltage change between live and neutral when the neutral is connected to earth.

Connecting neutral to earth will bring the neutral to the same potential as earth if there was a difference. But the L-N voltage should be the same, unless the neutral conductor had a problem.

This link must also mean you have no RCD on the sockets, which is not good either.

bothyhead

robbie7730 wrote: »

This link must also mean you have no RCD on the sockets, which is not good either.

Yeah, I'm all too aware. I got the consumer unit changed from the old milk-bottle type fuses a few years ago (the house was built in 1973). They had to bypass the RCD because it kept tripping. Now I know why. Hopefully electrician # 2 can sort it all out.

M cebee

crazy stuff

who does this type of work-bypassing rcds and linking N-E at sockets

totally off the wall

chrismon

bothyhead wrote: »

Yeah, I'm all too aware. I got the consumer unit changed from the old milk-bottle type fuses a few years ago (the house was built in 1973). They had to bypass the RCD because it kept tripping. Now I know why. Hopefully electrician # 2 can sort it all out.

The original sparky should not have left it like that.
Sounds dodgy.