Whole House Energy Monitor

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I just need to know the voltage to calibrate the Efergy when it gets here Monday, thank you Amazon Prime. From what I understand from the instruction manual tt defaults to 120 and from the UPS displays it appears that normal voltage coming into this place is 123-126. The transformer is in my front yard. Got my own personal transformer due to the fact they never built a planned road where half of my driveway is. 30 years ago. The line crews laugh when they see it serving one house.

I've got an Efergy. Well, it says Ematic on it but it's just a rebranded Efergy.

Works great, no issues in the couple years or so I've had it. You could measure your volts with a multimeter - think I used 240.
 
Here in the colonies we have two 120 volt legs coming into the main panel and have to put a sensor on each of them to be able to measure the 120 and 240 loads. The Efergy totals the current coming through the 120 legs. Presently the accuracy of the thing is awful. Which I am blaming on me for the moment and working on what I am missing. I had used the old unit on the meter long enough to know that the meter is accurate within 3%.
 
I use the efergy, it's been humming along for years. I constantly watch that thing and would be lost without it.

The sample rate is adjustable and I set it for every 6 seconds. That's just fine.

The voltage is adjustable. I measured mine and set it. This does matter since the efergy can only measure amps and then does a little calculation to make watts.

I've never downloaded the logged data but every day I check the day's usage against previous days usage with the buttons on the unit. I can tell when we baked in the oven or when we ran a load of laundry.

I find that the meter is very precise but only pretty good for accuracy. Meaning when a 12 watt LED bulb turns on, I see a 12 watt increase in the load. However, the display shows about 150 watts of flow when nothing is "on". Maybe phantom loads, maybe just a result of the sampling method. I see the difference in my monthly bill that is slightly lower than what the efergy tells me it should have been.

When you mount the little clamp on pickup coils, be sure to mount them as square to the wire as possible and on a straight section. They are measuring the magnetic fields generated by the flow of electrons which shoots out radially.
 
The sample rate is adjustable and I set it for every 6 seconds.
That's pretty good. I guess that's related to battery life.
The fact that you can relocate the display anywhere without interference would be an attraction to me.
 
Mine can only be adjusted for 10 or 20 second intervals. I wondered about the squareness of the induction units on the wire. One of them only had room to fit on a slightly curved section. I got in the habit of recording usage once a day over coffee years ago when the meter quit and the co-op stuck me for a ton estimating usage. I now have pretty much daily data back to mid-2008. Old and retired and don't have a real life, ya see.
 
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Little update. Measured no load circuits and saw that the best bet was to set the Efergy to 124 volts. For three days now it has been dead on with the meter. Liking this thing. Of course the Blueline was telling me the meter was measuring too high so I may have just adjusted the Efergy to do the same thing. <>
 
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Little update. Measured no load circuits and saw that the best bet was to set the Efergy to 124 volts. For three days now it has been dead on with the meter. Liking this thing. Of course the Blueline was telling me the meter was measuring too high so I may have just adjusted the Efergy to do the same thing. <>

To calibrate you can run a large 240 appliance with a known load like a 4500 watt water heater. Adjust the voltage input until the matching wattage is displayed.
 
To calibrate you can run a large 240 appliance with a known load like a 4500 watt water heater. Adjust the voltage input until the matching wattage is displayed.
Alas, this doesn't take into account the usage of the other customers on the feeder.
 
Not sure the other folks impact me since I am the only house on the transformer. May, but I don't know stuff like that.
 
Alas, this doesn't take into account the usage of the other customers on the feeder.
Alas, this doesn't take into account the usage of the other customers on the feeder.

It doesn't take into account the possibility of variable voltage at your house. I think that's what you really mean.

This monitor is designed to use a fixed voltage so you need to choose a test point and go with it. If your voltage varies a lot then this type of meter will be less accurate than if your voltage is constant. Pick a typical time of day when conditions are typical and run the test, determine the voltage and set the monitor.

It won't be perfect but it doesn't really have to be.

With a dedicated transformer he may be in better shape than most. Some are quite good at holding voltage and some suck.
 
It doesn't take into account the possibility of variable voltage at your house. I think that's what you really mean.
Load on FEEDER goes up, as in cold or hot weather, voltage sags, capacitors engage, or not, voltage bumps up, etc, etc.
 
bumping an old thread as I am interested in understanding my electric bill, and hopefully reducing it. I have been averaging 805 kWh/month, or 26 kWh/day. Electric appliances are two fridges, clothes dryer, radon fan, well pump, lights, and a few miscellaneous. Plus about 800 kWh total for summer air conditioning.

It's not clear to me whether the Efergy (or Energy Detective) monitors individual breaker circuits, or just the whole house draw? It seems like it would be difficult to identify an outlier load without know which circuit it is on. I would like to be able to track data over a period of time to know how much the dryer consumes vs. refrigerator, etc.
 
Effergy shows the whole house. Or, you could also clamp it on individual circuits if you can get the rings around each wire - might be possible on bigger circuits with larger wiring that is spaced a bit where it comes off the panel or where it hooks to whatever.

Doing whole house, usually what you'd do is shut a breaker off, or switch whatever off, and see how much the reading changes. That's what I did to determine that I had to do something about the flourescent tube fixtures in my office - they were costing me about $15/mo. About 1/6 of my total bill.
 
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ok, so I can turn off individual appliances and see the instant drop in power consumption. That works fine for steady resistive loads like lights, but what about intermittent loads like the air conditioner or refrigerator cycling on and off through the course of the day?
 
Refrigerator, you'd likely be better off with a receptacle type monitor. (I have one of those too). If the a/c is plug-in 120, might work for that too. But if it's 240 you'd have to get room around each of the black & red leads to get the Effergy clamps around. They aren't huge but they take some room.

EDIT: I think some also wire cycle timer thingies into their circuits, then you can tell the time it's run. Then you'd multiply that by how much power it draws when it's running.
 
Air conditioner is 240V, as are most high draw appliances I would be interested in monitoring.

The cycle timer would be fine for things with two power states (on/off) but PCs and other devices have a range of operating loads based on what they're doing at the time.

Those of you who have the Effergy- what have you used it for? Compared utility power draw to your measurement ? Reducing total demand? Identifying failing and faulty appliances?
 
I have an Effergy e2 classic. There are 2 sensor sizes available that go around the wires. It comes with the XL 200 amp sensor but you can buy the standard smaller 100 amp sensors. I installed the larger ones around my panels main cables. I then use the smaller sensors to monitor an individual circuit. You can only connect and monitor one sensor at a time though and you would have the 2 separate sensor wires coming out of your breaker panel. You just plug the transmitter into which sensor you want to monitor.

An example was I put the smaller 100 amp sensor on my GE Geospring heat pump hot water heater wires off the breaker and monitored that for a few weeks. In the summer I monitored my central a/c by moving the sensor to those wires. Very simple to monitor an individual circuit.

I found mine to be almost dead on to my meter and utility bill usage. You can literally turn on a 20 watt led bulb and watch the meter jump exactly 20 watts. My wife also leaves the electric oven on quite often by accident and I can't tell you how many times it would have been left on all night had I not glanced at the Effergy before I went to bed and saw 4500 watts being used.

http://efergy.com/us/products/accessories/
 
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I've recently moved the pickups for my efergy to look at just my Heat Pump Compressor, so I can monitor amp draw real time during a cycle and at different temps. (I am trying to diagnose some malfunctions, which I think are due to 'air' in the refrigerant).

If I wanted to know usage just for the HP I could use it for that too.
 
I forget, does the effergy log usage to a server, or itself, so you can analyze usage over time?
 
Does the Energy Detective continuous monitor and log individual circuits? That's what I would be interested in; so I have a "baseline" or what's normally happening in my house, then a quick glance will tell me that something is amiss on Circuit #18, etc.
 
I forget, does the effergy log usage to a server, or itself, so you can analyze usage over time?

As I recall, there is a USB port on the efergy to download data. Never did it though. It holds one week of daily kwh usage and a long term running average.
 
Those of you who have the Effergy- what have you used it for? Compared utility power draw to your measurement ? Reducing total demand? Identifying failing and faulty appliances?

Put in on the main feeders to monitor your actual consumption instantaneously and daily. I compared to the utility and it matched up pretty well. I use this data for several things. Reducing consumption is obvious, I know when something is on that shouldn't be. I also used it to identify faulty appliances since when everything is "off" I am still seeing current flow. My oven draws 50 watts all the time, no idea why.

I also own a clamp on ammeter to monitor the draw from each circuit if I suspect a problem but that doesn't log consumption.

The kill-a-watt is what you use for those 120 volt plug in devices.