Reading a digital meter

[Snozz]

I have a new digital meter on my little house. I am trying to figure out how much electricity is being drawn whenever most of my appliances are off. I used to be able to gauge this by how long it took one revolution of the wheel on the old meters. On this meter there is no wheel, just a LCD readout. It lists the kWh and a couple other things I don't recognize. It is a Elster, and has the identifiers Type2SD and also e239953, which I thought might have been model #'s, but I can't find anything on these, like a product manual.

[The Daring Dufas]

There are some folks in Florida who rebuild and sell new meters. Perhaps they could help you:

You may have a GE meter and here's some info.

TDD

[George]

It would seem you have the information you need. Record the start/stop meter reading and times for your observation. That tells you exactly how much usage was recorded over that interval.

[greenpjs]

You may be forgetting the time it takes for such an observation. Let's say his load when "most of his appliances are off" is 50 watts. That means the KWH indicator will bump up by 1 every 20 hours. Assuming, on average, it is half way to the next KWH when he starts to look, all he has to do is stare at the meter for 30 straight hours with all his appliances off! I think he was hoping someone would tell him there was a way to measure something smaller than 1 KWH.

[RickH]

If you are really concerned about modifying your electrical usage. You might want to consider a Brultech data collector:

Taking a single snapshot in time from your house meter really wont tell ou much about overall usage patterns.

[Alan W]

Some digital meters have a single LCD segment (usually a square block or arrow) that blinks once to correspond to one revolution of a mechanical meter. I think there might also be a second blinky that indicates some fraction of a revolution.

[Snozz]

Thanks everyone. Alan, I'll have to look again, but there was indeed some sort of blinking arrow which has a square block appear occasionally. That occurred to me, but I remember there was something strange about it, like sometimes two blocks or something like that. Can't remember. So I have to figure out how much watts that represents. I will be getting my utility to do a "free energy audit" after I get my house cleaned up some, and maybe they can clear things up for me.

[Don Young]

Thanks everyone. Alan, I'll have to look again, but there was indeed some sort of blinking arrow which has a square block appear occasionally. That occurred to me, but I remember there was something strange about it, like sometimes two blocks or something like that. Can't remember. So I have to figure out how much watts that represents. I will be getting my utility to do a "free energy audit" after I get my house cleaned up some, and maybe they can clear things up for me.

If you have some kind of indicator, the easiest way to get a rough calibration of it is to check it against a 100W light bulb. Just shut-off/disconnect everything else and see what your indicator shows for the light bulb alone.

Don Young

[HeyBub]

Make that a 100-watt incandescent bulb. CFLs will lie.

I've got a "60-watt" CFL, that draws 21 VAs but only registers 10 watts.

This is called "cheating the light company."

[greenpjs]

No, it isn't. The CFL only uses 10 watts of real power. However, it is true that because the current is somewhat out of phase with the voltage, it draws more current than an incandescent bulb would. (In more technical terms, its power factor is significantly less than 1). Power companies aren't thrilled with that situation because the losses in their lines ("i squared r" loss) is higher, but you aren't cheating them. The CFL uses 10 watts, not 21.