Drain on Electric Power Supply

[securespark]

Does your property have a solid floor on the ground floor?

Just thinking that if it does, it would be possible for anything upstairs/ in the loft to be connected to the GF ring final, either by accident or design.

 

[ban-all-sheds]

SO with a drain of 100 watts I would have to monitor the Meter for an hour to record 0.1 KWh

Well, next time your impatient (he/she has my sympathy) other half goes out, why don't you do that?

I'm assuming that nothing bad will happen in your house if you turn off all the other circuits for a couple of hours. So do that - take a meter reading, do stuff for a couple of hours that doesn't require electricity, and then take another reading.

 

[JohnD]

or you could sit and watch the red light to see if it flashes.

 

[ban-all-sheds]

That wouldn't tell him how much was being consumed, unless he did a pointlessly tedious job of counting flashes over a known time. And I get the feeling that he won't be happy if he doesn't know if his monitor and his meter agree.

 

[JohnD]

pointlessly tedious job of counting flashes over a known time.

timing the interval between two flashes is sufficient. You can time three or more to increase confidence.

"The majority of meters are labelled 1000 Imp/kWh which means that the LED will flash 1000 times for each kWh of electricity which passes through. The rate of the flashing of the LED tells you how much power is currently passing through the meter

One flash indicates 1Wh."

 

[Hysteresis]

Thanks again for all of the input.
This afternoon I spent a couple of hours determining that I had no other items connected to my downstairs ring. I eventually located a concealed fused spur which was supplying an upright freezer. The fused spur I had originally thought was for the freezer was in fact redundant. So i managed to get the power consumption down to zero with every outlet successfully isolated.
I then systematically switched each outlet on to see what was being consumed and what I found astounded me.
A Microwave oven in Standby consumed 85 watts.
A Fridge in standby, with no compressor running and door shut (no light on was confirmed) consumed 60 watts.
An Upright freezer with no compressor running and door shut consumed 50 watts.
Internet Router 45 watts.
Repeatable results were obtained by switching each item on and off several times.
These sorts of standby energy consumption figures was a big surprise and far greater that I would have expected. I may of course be unreasonably optimistic with the metering I am using and that measurement errors at low currents may be so inaccurate as to be useless.
Of course, talking to the manufacturers was pointless as the company representatives did not seem to understand what I was talking about.
John D provided a useful fact of 1 flash on the smart meter was equivalent to 1Wh. My meter is not labelled with 1000 Imp/KWh, but it sounds as if that would be a probable calibration.
So measuring 150 watts consumption with my crude metering system, I timed the pulse and got a result of 20 seconds therefore metering approx 180 watts. So bearing in mind my equipment using a domestic current transformer metering unit which will not be all that accurate, I think the result was reasonably conclusive in that the Time pulse measurement is within the margins of error one could expect from the equipment.
Anyone got any comments on the Standby Energy consumption from these devices.
I think it may be that my metering system is useless at such low values, which would account for the result that individual measured standby consumptions when added together and compared with the results with all devices connected together did not correspond, suggesting my system being useless at low currents.
Once again thanks to everyone for your useful and helpful comments.

 

[John D v2.0]

Think how hot your internet router would be getting if it was really using 45 watts!

 

[Hysteresis]

Fair comment JohnD, I instantly felt the router and it is warm but only just.
Rather confirms my unreasonable expectations of the low level capability of my rather crude Measurement system.
I think your pulse timing technique is far superior.
Thanks for the tip. Absolutely brilliant as I did not have the calibration details of the smart meter pulses.

 

[John D v2.0]

I'm not the original JohnD, I'm the later version!i know he'd be devastated that my comments could be attributed to him!

 

[winston1]

All those standby figures are clearly wrong. As I said earlier on those clip on energy monitors are not fit for purpose and should be banned. Many items in standby draw current at low power factor. So just measuring current will give a completely false result. To get a proper indication of power used get one of these:

http://www.maplin.co.uk/p/13a-plug-in-energy-saving-monitor-n67fu

It'll tell the power factor as well.

 

[endecotp]

A Microwave oven in Standby consumed 85 watts.
A Fridge in standby, with no compressor running and door shut (no light on was confirmed) consumed 60 watts.
An Upright freezer with no compressor running and door shut consumed 50 watts.
Internet Router 45 watts.

Absolute nonsense.

Get one of those plug-in meters; they are quite accurate for this sort of thing.

 

[endecotp]

There will be virtually no domestic device that is either Inductive or capacitive with a lower PF.

Where do you get that idea from?

 

[ban-all-sheds]

not fit for purpose and should be banned

Be careful what you wish for.

 

[ericmark]

I have a plug in energy meter, freezer running is only around 100W and when off yes it does use power, around the 450 mW mark, the worst item in my house was the Sky box in stand-by, they don't turn off the LNB so around the 10W mark, depending on the LNB draw.

 

[big-all]

remote energy monitors are well known to widely inaccurate with random 60w over reading being typical
please throw it away or use it as a novelty paperweight or at least use it where 600w plus are registered where any + or- error will be less misleading around 10%