Kill a watt, how accurate?

Let's add to your list of items requiring VA measurement. Virtually all electronics circuits that have an ac plug, have an ac to dc conversion that uses a diode/capacitor to get 170V dc (peak charge). These circuits have a non-linear current draw and therefore require the VA setting on the meter. TV's, converters, power supplies, and ac wall worsts will give an incorrect value when measuring watts.

MEXICOWANDERER wrote:

ken white wrote:
The VA feature is more useful than watts when trying to determine inverter draw/loads.

VARS incorporated.

Anything with a transformer, a coil, capacitor, meaning a reactive load needs to be measured in VARS and volt-amps is the way to do it.

A nail hit square on the head - amigo. Gracias

I just had to replace my Kill A Watt P4400 because it had gotten so inaccurate. I first noticed it about 6 months ago when it was just 2-3 volts off. Now it's as much as 10 volts higher than my Fluke.



I replaced it with a P4460, which is a few more $'s than the 4400. You can put your price per KWh in the 4460 and it does the cost calcs for you.



Close enough I'd say.

:):)

ken white wrote:
The VA feature is more useful than watts when trying to determine inverter draw/loads.

VARS incorporated.

Anything with a transformer, a coil, capacitor, meaning a reactive load needs to be measured in VARS and volt-amps is the way to do it.

A nail hit square on the head - amigo. Gracias

The VA feature is more useful than watts when trying to determine inverter draw/loads.

The Kill a watt is great.

I haven't tested the Auto drip coffee maker in the trailer yet but compared to the Bunn we use at home, it is loud and takes forever. The warming plate can't be turned off during the brewing process and adds to the draw even if we use a thermos after. Unlike the Bunn, it uses nothing when off.

I assumed the Bunn wouldn't work because it does keep the water ready and only takes 3 minutes to make a pot. Keeping the water hot would be negligible when the solar was running but be a drain over night. Testing it today showed me it only takes 33w to keep the water hot and 865w for 10 minutes to reheat the water since you don't have to have the 50w warming plate on.

So not only does the Bunn use less power to brew a pot than the Rival and we can handle the 3a a hour drain over night, it can do what the rival can't. I can make a pot silently when I get up predawn then turn it off and wait for sunrise to reheat the water.

Like I said, the Kill a watt is great.

Hi,

I added a watt meter so I can monitor all the power I use in the RV.

Before I had the magnum inverter I had no way to limit input on shore power connections so I'd "ramp up" slowly using the watt meter.

I noticed yesterday that the plug got really hot while the oil filled heater was plugged into it. As far as the inverter goes, the kill a watt is used here at home to test things before we go camping.

My Kill-A-Watt would get very hot when using it with my MSW inverter. It died after using it for a short while. An internal fuse had blown. It functioned fine when not using my inverter.

Well I have to admit, it's a fun little device to play with. It's surprising how much stuff draws power even while it is turned off.