back to line power meters

Kill-a-Watt:


This is a cheap tool almost anyone will find useful. Plug it into the wall and plug in your accessories to
it to view the device's current (amps), power (watts) or accumulated energy use over time. (watt-hours)

It's also helpful if you're connecting several items to one circuit and want to avoid an overload if all of
them happen to be on and drawing full power at the same time. Just test each device individually and find out
the maximum watts (or amps) it draws, then add them all together to see if you're going to get close to (or
over) the circuit's capacity.

And if you've got an inverter, it'll also tell you how much power an accessory draws, and you can use that to
calculate how long it (or any combination of accessories) can run on the inverter before the battery dies.

What I use it for:

- check to see if a battery is charging (expected Watts)
- check power draw (in Watts)
- measure energy use over time (in kWh)
- test for voltage drop on high-powered loads
- calculate monthly cost to run an appliance (you have to program it a bit with prices and run it awhile)

Press and hold the Function and Up buttons to clear the accumulated energy and cost readings. (the meter will
save the current readings when you unplug it and move it to a new location, so you need to be able to clear
these accumulated readings unless you want to be writing down the previous start values)

The first one I bought way back in the mid-90s I think? It doesn't have a display backlight so can be a little
difficult to read at times. I partly melted the front of the plug on this first one by running it on a 120v 25a
window air conditioner for awhile. It was well beyond its rated use, and a 120v plug gets really hot (like, melts
plastic hot) after it's been running for awhile. I bought a newer model of this meter so I could keep the old
(slightly melted) one permanently installed on my main server UPS in the basement.


Kill-a-Watt ($32 at Amazon)

kill-a-watt calibration.pdf


Kill-a-Watt:



highest resolution images
last updated 04/10/2025 at 09:16:58 by make_www_index.command version 2025.03.04.A