Owl or Smart monitor reading - which to believe?

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I have been using an OWL device which clips onto the live tail (meter to CU) and sends wireless reading to a remote display. Yesterday the meter installers gave me a display which reports lots of information about my usage and ongoing bill. (This communicates remotely with the meter). This morning the Owl reads 305W and the Smart sender reads 206W. Which do you think is correct? I'm only using a few lights, standbys and the TV at the moment so they are both credible. Could they possibly conflict?
 
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The Owl has a clamp meter and is not very accurate at low levels (a few hundred watts). And it only receives periodic signals. I have an idea that some loads, such as fridge and freezer compressor motors, are not very accurate. Larger, resistive loads such as heaters, are pretty good.

It is surprisingly accurate above 1kW (try switching on a 3kW kettle or immersion heater).

The smart meter is accurately calibrated and the definitive measure.
 
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Thanks John, that's as I suspected. Mrs Vicario will be in the 9KW shower soon so that should test the devices to see if the readings converge.
 
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Shower: 8758w on the Owl, 9160w on the Smart monitor in hot suds mode.
£1.89 an hour. Now where's that Eco setting?:LOL:
 
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I have been using an OWL device which clips onto the live tail (meter to CU) and sends wireless reading to a remote display. Yesterday the meter installers gave me a display which reports lots of information about my usage and ongoing bill. (This communicates remotely with the meter). This morning the Owl reads 305W and the Smart sender reads 206W. Which do you think is correct? I'm only using a few lights, standbys and the TV at the moment so they are both credible. Could they possibly conflict?

Your Smart Meter shows what you pay for and cost considerably more to design and manufacturer than the clip on. Iggnore the clip on, they only provide an approximate reading at best. Having said that, no meter is absolutely accurate, because how a meter responds to load, depends very much on the type of load. The easiest to measure are the straight forward resistive loads, inductive and loads like dimmers are much more difficult.

What really matters, is what you will be paying for, which is indicated by your Smart Meter.
 
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Shower: 8758w on the Owl, 9160w on the Smart monitor in hot suds mode.
£1.89 an hour. Now where's that Eco setting?:LOL:

Your Owl can only guess at the likely voltage, it only measure the current and calculates the likely wattage - your Smart Meter knows exactly what the voltage is. Amps x Volts = wattage.

So around 0.063p for a quick two minute shower. It's not the consumption, it is how long it is on for :)
 
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How many ladies (of any age) take a two-minute shower? Mrs V. likes to linger in there, wash her hair etc. It takes her more than two minutes to assemble all the potions and shampoos needed.;)
 
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How many ladies (of any age) take a two-minute shower? Mrs V. likes to linger in there, wash her hair etc. It takes her more than two minutes to assemble all the potions and shampoos needed.;)

Sneak in and turn it to cold after her two minutes are up :)
 
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Or one those fk'n annoying push buttons you get at the gym. And, assemble all the potions before turning the water on. I personally rarely go over 5 minutes.
 
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the Owl enables you to set voltage. Mine is always around 240v so I set it to that. If it was set to 230v or 220v it would under-report watts used.

its purpose is not to calculate your bill.

It's purpose is to show you (about) what you are using.

I can even look at mine during the night and will know if any lights have been left on downstairs, and when the frost-protection heater for the garage plumbing has come on.
 
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the Owl enables you to set voltage. Mine is always around 240v so I set it to that. If it was set to 230v or 220v it would under-report watts used.

its purpose is not to calculate your bill.

It's purpose is to show you (about) what you are using.

I can even look at mine during the night and will know if any lights have been left on downstairs.

Checked mine when I moved in here 2½ year ago. It was 258v. I forgot to check that again since...Old houses (1884), forgotten with time.
 
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mine is currently 242.23

slightly boosted because it's cold and sunny and the solar panels are making about 1kW
 
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the Owl enables you to set voltage. Mine is always around 240v so I set it to that. If it was set to 230v or 220v it would under-report watts used.

Even so, clamp on metering is not a 100% accurate way to measure current - they give a good indication. Try waggling the jaws about and see the values change.
 
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