Do electricity meters fail?

[J@mes]

I have a customer who has just had a bill land on his mat for £16000 in a year - 55000KWH used according to the meter which has jumped from 27000KWH to 82000KWH in the space of a year on the Normal reading, and the LOW reading has seen an increase of around 15000KWH too.

It's on a farm which is quite small (about 5 buildings, 2 barns which contain 1 37KW drying motor and 1 30KW motor) and that's about it.

I've been up there today looking for signs of faults, but there isn't anything. The motors draw the expected current on start up and running, but obviously I haven't been able to do a long term test, other than measuring the currents on each phase for 5 minutes, there is no power usage on the domestic electrics which could be considered to be out of the ordinary either.

The only thing I could suggest to the customer was that the meter was faulty/ out of calibration. The readings are correct as he takes them himself and sends them off, keeping records of them. Normal usage over the course of a year is about 4000KWH, since 2003, up until 2008 where it suddenly jumped up.

Ideas/ Opinions?

Thanks

 

[jpmiff]

how often does he take the consumption readings?
He may see a trend or when they started to go higher than normal.
has any one been working on the supply transformers and change the voltage tappings?

 

[oldtimer]

He needs to be taking a meter reading every week or month now you may think how will he remember but he can set up a reminder either on his phone or email software. If he can put them on a spread sheet then he can police his consumption

 

[Darkwood]

you've got 37 and 30 kw loads you mentioned, how often and whats the duration of use on these?

 

[Darkwood]

you've got 37 and 30 kw loads you mentioned, how often and whats the duration of use on these?, i take it the are 3ph not 1ph as you havent mentioned. If these can be omitted as they may not be used often then like above mentioned you need to check when the last actual measurment was taken as the energy supplier may have spent years estimating and getting it wrong by a margin that has just been realised when the actual reading was given to them for last years usage.

 

[J@mes]

Consumption:

2003 - 2007 was done yearly, and showed a rise of around 4000KWH a year.
2008-2009 was done 3 monthly, and showed the same
June 2009 - June2010 was done over a year and showed the huge rise.
Monthly since June 2010.

He has the exact figures which I may ask for to look over and see if I can spot any patterns, but I spent an hour with him today looking at what crops he had in the driers, what the weather was for those times, whether the crop was harvested wet, how long it needed drying for (he has to keep records of all this for the people he supplies the grain to) and it all looked to be normal - it's been a good year and the driers have not been running much at all.

The motors have been used, but here is the strange thing - in the 3 months when they were not being used there was a huge jump in consumption - 8000KWH. in the month they have been used for 12 hours a day (although not every day), the consumption has gone up by 300KWH a month which is expected.

The customer will now be taking daily logs of the meter readings and keeping "hours run" logs of the two motors to see what they are doing.

I've known the customer for 3 years, he is honest, hard working and pays up without any issue at all. I have no reason to suspect that he is pulling a fast one.

No-one has tapped his supply, he's at least a mile from the nearest village/ hamlet.

Not sure if anyone has been working on the supply, but my readings for when I started working for him 3 years ago and today are around the same, 437v 3P and 235v 1P.

The supplier are sending someone to check the meter in the next week or so, and I have advised that if the meters come back as fine that the two drier motors are sent away for testing.

Thanks so far!

 

[jpmiff]

Hi

let us know how you get on

 

[antimatter]

I used to install electricity meters and quite often had to install "check meters" which is another meter running along side the original meter.

Readings are taken from both meters for a period of 2 months.

When I have returned to remove the check meters, the customers are always "red faced" when they see that what I was saying is right, they hardly ever fail, they are calibrated at the factory and the new digital meters regulate and check themselves electronically, so the margin for error is pretty much non-existent.

The only thing I can suggest if the customer has recently changed supplies and the have incorrect previous readings for the old meter. That would explain the sudden "jump" in readings.

 

[J@mes]

There has been no change in supplier since 2003 when the meter was installed, and it is not a case of incorrect/ estimated readings as the readings have been taken at specified times, just in the last year the consumption has apparently gone up massively for no reason.

Very odd, but as said I have no reason to believe the customer is trying to rip the supplier off. He as even said that "if he has used it, he will pay for it" but can't understand how he could have used that much electricity, bearing in mind it has been 10 times the amount for previous years!

Thanks for the replies, keep them coming!

 

[rocker]

Bet it's something like heating elements in one of the fan driers not shutting down or something.

 

[J@mes]

The driers pump air direct from gas burners in to the drying tunnel, so no electric heating

 

[brasspark1]

I used to fit electricity meters to, and although as antimatter say it is very rare that the new digital meters fail, BUT I HAVE KNOWN THEM TO. I would ask the supplier to fit a check meter ( if there is found to be no fault with the meter there will be a small charge ) because that amount of an increase does sound as though it is a meter fault.

 

[specialdog]

I have also fitted check meters on digital meters in the past and would agree with brasspark1. 999/1000 there is no fault at meter but it does happen. You could check load on meter simply by turning everything off on the main board apart from main switch and checking the load light on front of meter to see if its flashing rapidly.