ATA mains power meters

[moz]

Forgive me if this is not quite the right area, but I have a one-step-out-of-the-mud mains power meter - the wee gizmos that plug into a power point and you plug your load into the back of it. The $20 supermarket jobs are accurate to give or take 5 watts ish (I have one of those too), but the Alternative Technology Association (ATA) sell a slightly better unit. Starting from $120: https://shop.ata.org.au/shop/power-mate-lite  Manufactured by Legend in Australia.

Apparently "Accuracy error for all ranges is below 2%, (typical accuracy is below 1%)" ... I was hoping someone here would already have reviewed one and expressed opinions on the accuracy. Specifically, just how accurate are they at low power levels, for say comparing plug-in USB power supplies?

[Kleinstein]

Measuring low power devices like USB supplies or wall warts is tricky with these single range power meters. The usual cheap ones are not really good below 5 W - some are worse than others and and the price is not a good indication of the quality.

With the linked unit, the price is rather high, but the specs are not much different what you expect from the cheap $20 units. Having an extra Greenhouse gas scale makes me even a little suspicious that the extra price may be because of this. At least the specs don't give much hope this meter will work well for small units like an USB supply.

[ap]

If you want to measure low power with good accuracy, I would recommend a used metrahit 29s. Lowest range 1mW, up to 10kW (details see data sheet). And you can use this also for lots of other measurements. Pretty good meter. Usually sells in the 300 euro range used. You just need a small adapter box for convenience.

[Assafl]

+1 on the metrahit 29s. The power reading works well.

[moz]

Thanks... but I'm just wandering around the house whining about stuff not being turned off, rather than doing anything that would justify spending 300 Euro. I'd kinda like the expensive meter, but I'd feel like a bit of an idiot with it because I'd only ever use 1% of its functionality and would probably have to re-read the manual every time I used it.

I'm more likely to buy a scope and grind the information out of that than buy a pricey multimeter.

[quarks]

have a look here

https://www.eevblog.com/forum/projects/measuring-standby-power/msg413158/#msg413158

https://www.eevblog.com/forum/testgear/yokogawa-cw-10/msg396901/#msg396901

[moz]

Thanks, I knew there would be something but obviously failed to find it. Now to hack my cheap meter