Portable Power Meters

[Hans Tucker]

Anyone use Portable Power Meter to check out which domestic devices are consuming the most power? Are these meters accurate? What brands are the best?

[OffGrid]

G'day Hans,
I am on my second unit which is called an Energy Watch Monitor by Watts Clever available from Jaycar. This one comes with a handy short extension lead which makes for much ease of use.
My first unit of around 10 years ago is missing in action as I had loaned it out to friends and colleagues so often, I now cannot recall who had it last.

Purchased it mainly to check residual ( standby ) consumption and also cost of various cooking equipment.
Just 2 weeks ago I was amazed to find how cheap slow cookers are to run on low all day, like about 27 cents for 10 hours.
Main benefit to standby monitoring was to turn off all power to entertainment unit and computer, router and moden when not being used.
Will check my fridge next over a week and compare it to a summer reading.
I do not have any means to assess accuracy and have not been exposed to other types or brands.
I am happy with this unit as I have recovered the cost and then some, buy changing consumption habits and using more efficient cooking methods.

I also have a 12 volt DC WattMeter that I use to monitor Astro gear which to me is critical due to battery storage and battery life limitations.

Steve

[inertia8]

I've used the Jaycar one from about 5-7years back, it's accuracy was questionable when below 30watts or so, therefore not great for standby.

I have confirmed it's accuracy against stated consumption values on some old heaters (700w/1400w), a pond pump (192w) and a air pump (80w) and my networking hardware with NAS (30-40w, in agreement with the front panel of my UPS.).

I'd be interested in standby, but I think our issue is too many fridges/freezers and pond pumps, these all go 24/7. Timers are going to be used but it's a bit tricky with bacteria in filters dying relatively fast if water isn't flowing over the media.

[GrampianStars]

G'day Hans
I don't bother with the AC readings
as I'm down to 6-7 Kwh /day according to the Sunny Boy Inverter
I use the Turnigy meter to monitor my dc usage and monitor batteries
http://www.hobbyking.com/hobbyking/store/__10080__Turnigy_130A_Watt_Meter_an d_Power_Analyzer.html
:thumbsup:

[The_bluester]

I always read that the plug in power meters are pretty questionable below about 30 watts so I used a clamp ammeter on an old extension cord which has the sheath stripped off so you can access the (Still insulated) active or neutral conductors inside. You have to measure on one only as the current flow one way is cancelled out by the current flow the other if you do not and you read zero. Then a pretty easy calculation of P=IR (Making a basic assumption that input voltage was 240VAC)

It led to a round of rationalisation of gear and changes to home theater PCs to units which consumed a whole lot less power. Converting a desktop PC to use as a HTPC is really power hungry! The units I use now (Intel NUC) use less power in operation streaming video than a desktop machine at idle!

[glend]

The Power Metres use power as well don't they? I just make sure everything is turned off at the wall switch if I am not using it, no warm start stuff for me. Also only ever use major appliance power during the day when my solar panels are generating enough to cover the appliance draw. And only use one appliance at a time so that you don't draw from the grid, ie don't run the washing machine and the microwave at the same time. Takes a little discipline but probably would not work in a house with more than one person - especially when they could not be bothered. Bring on the Tesla PowerWall battery system!