monitoring 2 circuits

[wjquigs]

My monitor didn’t match my electricity bill and Emporia support helped by informing me that the monitor wasn’t plugged into both phases in my panel. So that’s fixed but I have a couple of follow-on questions. I have a lot of circuits and am monitoring my 230V circuits with 2 CTs each (because they’re imbalanced). Some of my 115V CTs cover 2 breakers. If I’m going to run 2 wires through a single CT, do those wires/breakers have to be on the same phase for it to measure accurately? In other words, can I monitor 2 adjacent breakers with the same CT or do I need to go to the next breaker up/down to get on the same phase? My balance is still 6% after correcting phase, and I have monitors on all circuits except the ones with almost no load, so I’m suspicious something is still amiss.

Second, for those who are monitoring 230V appliances with imbalanced load, at what point do you take one of the CTs off the second leg and change your multiplier in the UI? For example, my heat pump air handler in the attic consumes 8% of the total electricity of (heat pump attic+heat pump outside). Will this typically remain constant over time (I had to reset the Emporia a month ago to address the phase change so I don’t have a lot of history). Same question for water heater and spa, which are imbalanced by 17% and 43%, respectively. Has anyone monitored for long enough to determine where the “long tail” starts? 1 week, 1 month, 1 year?

Third, I’m assuming there’s still not a way to add the output from 2 CTs so I can just have one line “water heater” and not “water heater 1” and “water heater 2”, correct?

 

 

[Azazel1024]

I’d double check that those unmonitored circuits really have almost no load on them. For example, one circuit I am monitoring it took me awhile to track down what was mysteriously using around 50w of power, even with everything unplugged. Then it hit me that my radon exhaust fans were on that circuit.

 

How is the heat pump setup? One circuit for both the air handler and the compressor (outdoor unit)? Most installs I see, the air handler is on its own, usually 240v, circuit and the compressor/outdoor unit is on its own dedicated 240v circuit. I’ve seen a few rare instances where compressor or air handler use split phase 120/240v three wire installs where you’d want to monitor both legs, but the vast majority have been single phase, 240v two wire installs and you only need to monitor one wire. If you are monitoring both legs of a 240v single phase. Do you have a white wire, likely re-colored with black or red tape on it, along with a black wire inserted into the dual pole breaker with no neutral going to the neutral bus bar? Or is there actually a red and black wire in the dual pole breaker and a white headed to the neutral bus bar for the wire headed to the appliance? If you are seeing an 8% imbalance, let alone a 17% on the water heater, there is something else going on. Water heaters are almost universally 240v only, so the legs should be in balance, not unbalanced. The current only has one path.

Two things to check, are the CTs facing the correct direction. It is labeled on each one. There is nothing else running through the CT or right next to it. For example, I noticed when I set one up, that the power was suspiciously high. Then I looked and one of the sensor wires from another CT was almost run in to the CT for another circuit. I moved the wire that was kind of just at the other CT and the measurement dropped. Other tinkering did nothing, but if I took the other sensor wire and stuck it right along the CT, it would cause the reading to jump a little (a few watts).

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