Light circuit drawing power

robj20

robj20

robj20

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Joined
9 Apr 2007
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Right moved into a house, one of the light circuits is drawing power even with the lights off. So far i have narrowed it down to the garage lights, fluorescent tubes and kitchen normal bulbs.
I have remove the tubes and totally removed the kitchen fitting and changed the kitchen light switch as it was very stiff it still draws power though. Not sure how else i can narrow it down.

For the time being ive switched the mcb off.
 
How much power are we talking? Personally I'd put it all back together and forget about it unless it is going to cost you a significant amount of money!
 
if your really serious then it's time to start tracing wires to find out what if anything else that circuit is feeding that is shouldn't as I don't see how two disconnected lights could be drawing anything!

Does the meter disc stop if you turn that circuit off?
 
Odd! Try removing the fittings and just leaving a choc block hanging and reconnect one at a time to rule out the fittings having a fault.
 
It should say on your meter the amount of power used per revolution. In the image below it says 250 revolutions per KWh. Yours must be different otherwise I calculate your lighting circuit is pulling 2.9KW!

3600s per hour / 5s per rev = 720 revs per hour

720 revs / 250 revs per KWh = 2.88KWh used every hour.

2.88KW ~= 12Amps which is double the current rating of a standard 6A lighting circuit.

In summary we need the details off your meter :p


kS7RymI.jpg
 
Have you got any power sockets in the garage? Someone might have bodge spurred off the lighting circuit to run a fridge/freezer/tumble drier etc.
 
There are sockets but nothing plugged in anywhere, just moved in so only the boiler is on but that's on its own circuit. I may try taking the tube fittings off, the kitchen light fitting has been removed just a hanging choc block at the minute. Will have a look at the meter tonight.

Plan for when i have time is to remove the bottom of the consumer unit and see how many wires i have leaving the mcb, if there are more than one remove them one at a time until i find the problem one and then follow it.
 
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I just rewired my crazy house that had spurred cables off the lights going to things I cant even explain. The cooker was on the upstairs lights (cooker is downstairs).... I wondered why it kept blowing the fuse!

Also the living room lights also did the lights in the shed and the lights & sockets in the gym.

Are the fluorescent tubes controlled via normal light switch or is there an actual switch on the light itself. If there is a transformer in that light then it will still draw power when bulb is removed (I think)

Apart from that I agree with kefkef, could be some spurred cables going elsewhere.

I hate electrics....but not as much as plumbing!
 
Shaver socket charging toothbrush?

outside lights, pir sensor might use abit, os light tend to come on when you turn the mcb on but would go off within a few mins, does the meter go faster when you first turn the mcb on then slower a few mins later?

Garage lights? have they taken power for a garage door opener from the lights?

Tv / aerial booster/splitter or socket in loft?

Could be a small fault not enough to blow the mcb but wasting power, has lighting circuit got rcd protection or more likely just mcb, in theory could leak 1kw with a fault and not trip, if rcd protection then it cant have a significant fault or rcd would trip
 
The outside light bit is a good idea there are a couple, that's what i will look for next.

The wiring throughout is a bit of a bodge in places, came across a dual light switch with 4 wires with one looped across making 5 connections and they are all red. I'm confident doing things like adding a spur or extending a ring main but lighting is just annoying me.

And the meter is 200 revs / kwh.
 
robj20 said:
The wiring throughout is a bit of a bodge in places, came across a dual light switch with 4 wires with one looped across making 5 connections and they are all red.
Click to expand...

That's not a bodge, it's quite common to have the permanent live looped at a switch like that.
 
The bodge is having all wires identical, no marking no colour coding, plus a wooden back box, never seen that before.

I cant for the life of me figure out how to wire it all up, i can get one light working but not both.
 
robj20 said:
And the meter is 200 revs / kwh.
Click to expand...
At 5 seconds per revolution that implies a continuous load of 3.5kW. It definitely says per kWh not per Wh?

Have you got a hot water cylinder and electric immersion heater in it? They are generally 3kW. Maybe check the loft for a hydroponic pot operation!

What is the circuit breaker on that circuit rated at? Lighting are normally B6.

I find it hard to believe you could have a 3kW load which implies a measurement/calculation error or meter fault.

Take a meter reading before work tomorrow then another when you get home noting the times of each reading.

I would expect you to use under 1 kWh with just the fridge and standby electronics on.

On the other hand if you do have a 3kW load your meter will report 30kWh over 10 hours.

/edit or you could just monitor it hourly tonight. A load that large with be easy to distinguish.
 
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Is this a detached house or semi? My friend moved into a house and found out that the neighbour had wired his hot water heater into his supply lol.
 
Found it was three outdoor security lights. Hidden switch in the garage. Having only tried to find it during the day I didn't notice they were on. Thanks for all the input I would have been guessing for ages.
 
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