Meters disagreeing

Sponsored Links
I would have thought that the OWL wasnt calibrated either, I would expect the Actual meter to be calibrated to within 1 or 2 %? I know at work we calibrate ours to 0.5% for digital and 2% for analogue in terms of accuracy but i doubt the electricity companies go that far...or do they?
 
In the nationalised days we went for far greater accuracy that the limits available, usually within 0.5%
 
Sponsored Links
I would have thought that the OWL wasnt calibrated either, I would expect the Actual meter to be calibrated to within 1 or 2 %? I know at work we calibrate ours to 0.5% for digital and 2% for analogue in terms of accuracy but i doubt the electricity companies go that far...or do they?
That may be true, but it's not difficult to manufacture and calibrate pretty accurate measuring devices these days, so I would not be surprised if the OWL were pretty accurate in terms of current measurements, quite possibly not appreciably worse than any other non-contact current measurement device. However, as I keep saying, one of the greatest problems is that it is only a current measuring device, and therefore cannot possibly be expected to be as accurate or reliable in the field at presenting 'kWh' figures in comparison with a proper kWh meter, which does it properly.

Kind Regards, John.
 
Also, I have noticed often how the OWL meter is showing current, which the L&G meter says there is none. Is the anti-creep mode the reason for this?
Current or power - they are two different quantities.

It is actually very easy to get a basic monitor like the Owl to show a reading while a real power meter shows none. Just connect an inductive or capacitive load and you'll get current, but no real power - the power meter is correct, the current indicator is misleading. When you have "no load" on, you probably have a number of small loads running - power supplies for various stuff - and these are often very poor power factor when unloaded (eg a transformer-rectifier PSU is mostly inductive with no load).
Recently, in a letter to Which? someone commented that after switching everything off, his boiler was "taking 40W" according to one of these monitors and commenting that this didn't seem very green :rolleyes: I bet it had a transformer-rectifier PSU and was just presenting an inductive load.

I believe this is where some of the old wives tales about chargers and stuff taking the same power when not charging your phone as when it is - someone had measured the current, knows f**k-all about electricity, and declared it to be taking power.

hence why it is called a monitor not a meter.......
Well, to be fair, 'monitor' usually implies some sort of measurement device which measures continuously, or undertakes a continuous series of measurements, rather than necessarily implying anything about accuracy (some 'monitoring devices', particularly in safety-critical areas, can be extremely accurate) ....
"Indicator" comes more to mind.
 
hence why it is called a monitor not a meter.......
Well, to be fair, 'monitor' usually implies some sort of measurement device which measures continuously, or undertakes a continuous series of measurements, rather than necessarily implying anything about accuracy (some 'monitoring devices', particularly in safety-critical areas, can be extremely accurate) ....
"Indicator" comes more to mind.
Indeed - 'indicator'would seem to be a very good ford for a device which gives an indication of the magnitude of a quantity, rathere than necessarily an accurate measurement thereof.

However, to repeat what I've said before, I suspect that these OWL-like devices are probably as good as many non-contact devices at measuring current - but their conversion to the Energy (kWh) which they display is very iffy! So, maybe they qualify as current meters but energy indicators :)

Kind Regards, John.

Kind Regards, John
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top