Who is using my electricity - meter spinning no mcbs on

[dmcclymont]

" we had to snip the main 100A FUSE security tab to get it out. "

No, you did not, the last owners of the house must have done it!!

 

[dazzlerpalmer]

I switch the double pole switch & all mcbs & rds off.
The disk spins as slowly as is humanly possible to see.
100 times slower than a 100watt light bulb

it is so slow that you have to rest your head fixed and eyeball it.

It is so slow that if you glanced at it you would say it has stopped.

Strange since I would imagine however the board was wired switchinig off the double pole switch would break both connections?

 

[mapj1]

If it really is 100 times slower than the 100watt lightbulb, at 5mA its probably the meters own consumption, and nothing to worry about.

 

[jim4bb]

If it really is 100 times slower than the 100watt lightbulb, at 5mA its probably the meters own consumption, and nothing to worry about.

I know this may sound stupid but someone hasn't wired the door bell transformer straight off the incoming supply as opposed to from one of the outputs. Probably only about ten watts I would suppose.

Sadly found this website where somone measured his minimum load in his house gives a few calculations. I wouldn't have the time.

click me
__________________
moderator

edited to correct link

 

[dazzlerpalmer]

Now we are getting more information! When you say you recently changed the board, I am assuming that you carried out all the necessary testing ie. loop impedance, R1+R2, Ze, Insulation, RCD times etc of each circuit as you went? How experienced are you as this is not normally a recommended DIY job and can you be sure you have carried it out correctly? A faulty meter is less likely than a fault introduced fitting a new CU without proper testing.

Point taken, although how could the wiring have any bearing on power consumption when the double pole switch is off? Or when all mcbs are off?
Give me an example of faulty wiring where these two conditions means power consumption. I replaced all the wires into the correct places 100 times neater than the rats nest that was in there before.

BTW thanks for all the replies, most helpful

 

[ban-all-sheds]

A faulty meter is less likely than a fault introduced fitting a new CU without proper testing.

That's almost complete b****cks.

Without the testing you mention then existing faults will go undetected.

Without the testing you mention, existing faults may manifest themselves in nuisance trips.

Without the testing you mention, existing deficiencies will remain undetected, and the installation will retain its below-spec characteristics.

But introducing a fault simply by changing a CU? How so?

 

[dazzlerpalmer]

I Agree with the last post.
Any existing faults (outside the consumer unit) will still be present once the new consumer unit has been installed. In actual fact it may highlight faults because the old CU had not RCD. The new one has.

My question is this.

What type of fault could cause power to be consumed when ALL MCBs are switched off. Whilst the consumer unit is still being fed from the main switch, all the mcbs are off. I am sure there must be a way power is consumed in this scenario but cannot picture it.

It is a split board. All the lives (reds) are going into the bottoms of the MCBs, the neutrals (blacks) are in the appropriate N blocks.
All connection are tight. Surely the break in the circuits (MCBS off) would cease all power consumption.

Confused!

 

[mapj1]

Are you saying that with all MCBS off, but the main incomer switch on, the meter rotates, but with that double pole switch in the off position, it doesn't?
If so I am puzzled too, as if the meter was drifting from its internal consumption alone, then that would be independant of the position of the main incoming switch. Unless there is some odd neutral current problem - remermber the MCBs only interrupt live, but the main switch interrupts both live and neutral. So a current in the earth-neutral path, either from your supply or the neighbours could just about have an effect, but it would require an odd combination of wiring errors.
(or in a fit of insanity, something is wired onto the live after the main switch, but onto the incoming side of the MCBs - but I assume that is not the case - the live output of the main switch goes to the live inputs of all the MCBs, and nowhere else, and all the final circuit live feeds are fed from the output sides of MCBs only)

I presume all the MCBS work - that is to say when operated by hand the relevent circuit goes off and on as expected, and nothing else.- an MCB stuck "on" is very unlikely, but perhaps one bridged internally by a strand of wire offcut dropping into the works is just possible.
Please confirm what you see.
regards M.

 

[BJS_Spark]

That's almost complete b****cks.

Thanks for that rudeness BAS!

But introducing a fault simply by changing a CU? How so?

Don't know about anyone else on here but I can think of hundreds of ways of introducing a fault when changing a CU if done badly!!
Possibly...

It is a split board. All the lives (reds) are going into the bottoms of the MCBs, the neutrals (blacks) are in the appropriate N blocks.

Surely you do mean the tops of the MCB's dazzler??

 

[ban-all-sheds]

That's almost complete b****cks.

Thanks for that rudeness BAS!

Don't be so precious..

But introducing a fault simply by changing a CU? How so?

Don't know about anyone else on here but I can think of hundreds of ways of introducing a fault when changing a CU if done badly!!

Hundreds! Blimey...

How about just giving us the most likely 10% - please assume that a very careful replacement job was done, and there are no circuits with the wrong MCBs, no neutrals on the wrong side of the split, no rings coming out of two MCBs, no lessening of RCD protection, no screws going onto insulation instead of copper, no reversed polarity, no loose screws.....

Possibly...

It is a split board. All the lives (reds) are going into the bottoms of the MCBs, the neutrals (blacks) are in the appropriate N blocks.

Surely you do mean the tops of the MCB's dazzler??

Unless this is his board:

 

[BJS_Spark]

Surely the point is you only need to introduce one minor fault to create a dangerous installation, which on a job like changing a CU is more likely to effect the installation as a whole.
I personally would never assume a job was up to standard unless I checked it out with proper test instruments instead of guessing that it was Ok!!

 

[dazzlerpalmer]

I changed like for like (connection wise)
Although it is on a split board I put all on the RCD side leaving two spare mcb holders.

The bus bar was tightenening on all mcbs
The reds went into the tops of mcbs
I checked all the connection were tight on the copper.
Made sure no lose dust/debris anywhere
Identified all circuits and put a notice next to the fuse board.

It is a million times neater/safer than what was there. (some of the old terminals had loose screws and unsheathed earth. Some of the lives were cut back too much or too tight etc.

Thanks for all the useful advise. When I asked about what sort of errors switching like for like could create I did not mean the actual mechanics of the switchover obviously I could put the wrong wire in the wrong terminal of introduce copper waste into the connections. I was more interested/bemused as to what types of problems in the circuits away from the CU could exist.


I am happier that the whole system is now RCD protected though. I know the lighting circuit should not realy be on it but I personally think that as I will be working on the house alot until it is complete better safe than sorry.

Now I have done the work though I will pay a spark just to sign it off and check it. Then I will have complete piece of mind.

Thanks again

 

[ban-all-sheds]

Surely the point is you only need to introduce one minor fault to create a dangerous installation, which on a job like changing a CU is more likely to effect the installation as a whole.

OK - come on then - let's have your list of hundreds of faults that you could introduce downstream of a CU by simply replacing a CU.