Meter spinning with power off

Effects

Took a look at a meter for some friends complaining of a high electricity bill. It's an old Georgian house converted into flats. There's two consumer units in the flat and two isolators at the panel downstairs so I'm assuming it was running on two separate meters at one stage. With both isolators switched off and no power going to the flat the meter is still spinning, although it is quite slow. Would this suggest that the meter might not be accurate while it is in normal operation leading to higher bills? Is there possibly a tap into their supply before the isolator which is causing the meter to spin, slowly last night but possibly higher if something else is running at a given time?
Any thoughts much appreciated.

mikehammer67

it shouldn't spin if there's nothing on it

Tow

The meter is supplying something else (does it speed up when they turn everything on?) as well. It may well be powering lighting in the common areas, someone is tapping it or is not their meter at all. There was another similar thread a few months back but the mods closed it before the OP could give us the outcome of the ESB's investigations.

Effects

They had already contacted the ESB and they said to get an electrician to look at it. That's why I took a look. It's definitely their meter.

Davy

How long did you leave the isolators off for?

Effects

15 minutes or so. Does it need longer?

Philip82

If you disconnect the mains from the distribution board in the flat it should be completely dead and the wheel cannot spin.
If it does however then you have like the guys said either a faulty Meter (never seen one before) or somebody is tapping into the meter. Also make sure the isolation switch is working as it should and that its not leaking voltage through to the meter.

mikehammer67

Effects wrote: »

15 minutes or so. Does it need longer?

no
they won't spin when there's no connected load

not that i ever heard of anyhow

hufpc8w3adnk65

Perhaps as stated the landlords supply is fed from this and it is powering landing lighting or outdoor lights or something?

adrian92

Extremely unlikely a faulty ESB meter. I would rule that out.

There would appear to be some connected load between the meter and the flat.

Could be a tricky thing to find out exactly in an old building - I have a sense of the arrangement.

If there would be some way that the flat could be left entirely vacant for a day or two and all power definately off - note meter reading before and after. If there has been some electricity recorded on the meter then possibly give this evidence to landlord to get checked out.

Someone may be tapping in - especially if there is a long run between the meter and the flat. But , of course, I would not suggest that anyone would do such a thingg

Imported but

Effects wrote: »

They had already contacted the ESB and they said to get an electrician to look at it. That's why I took a look. It's definitely their meter.

Can you get an idea of how slowly it's turning with everything off - is the current loss less than 1 A or more than 5 A? Either take the two-readings (approach suggested above), or time a rotation (in seconds) and look for the rotation-per-unit factor on the faceplate of the meter (maybe about 250): the power indicated is then gotten by

'g' = 3600 divided by your factor: something like 250 let's say. (If 250, then 'g' equals 14.4)

Power in kW = 'g' divided by time-per-rotation (in seconds)

Assuming 230 V supply, your current in A is then the power in kW divided by 0.23

E.g. (assuming 250 rot/unit) if a rotation took 10s, power would be 14.4/10 = 1.44 kW and current would be 6.3 A

We have some 'original' wiring in our place (i.e. fitted when electricity became available) and the insulation on that stuff can be perished. Combine a lack of insulation with a possibility of debris (and moisture - is it damp?) behind the fuseboard, and you might have small amount of current leakage.

2011

Effects wrote: »

Took a look at a meter for some friends complaining of a high electricity bill. It's an old Georgian house converted into flats. There's two consumer units in the flat and two isolators at the panel downstairs so I'm assuming it was running on two separate meters at one stage. With both isolators switched off and no power going to the flat the meter is still spinning, although it is quite slow. Would this suggest that the meter might not be accurate while it is in normal operation leading to higher bills? Is there possibly a tap into their supply before the isolator which is causing the meter to spin, slowly last night but possibly higher if something else is running at a given time?
Any thoughts much appreciated.

With both isolators off measure the current at the meter with a high quality (such as Fluke) grip on ammeter.

Depending on the result you could consider replacing the mains supply cables from the meter to each consumer unit.

Bruthal

Yea a grip ammeter would be the thing to use alright, try it on the live first on its own, then same on neutral, and see do any readings match.

ted1

I've found faulty meters before,
But usually there's a load tapped off, is the meter far from the consumer unit?

Effects

Thanks for the replies. I'll see if both tenants will be away some time soon and get before and after readings to see if anything shoes up.
I hadn't thought about small leakage from bad insulation. The meter is on the ground floor at the front and the flat is on the second floor at the back. I've been using a Fluke T5 and the readings were small enough but I thought if something is tapped then it might not be on all the time.

mikehammer67

so how far apart are the meters and isolators?


are they in the same location? or maybe i'm misunderstanding