Good Morning,
I’ve had my Itowatt a few years now and just installed a couple inverter duty mini-splits heat/air. They are 220 connected to a sub panel and I am measuring both legs to the panel with two ECS1050 plugged into a 3.5 splitter and it plugged into 1 input on the Iotawatt. My amps have always been 2 amps higher. Even when minis-spits are turned off itowatt reports 2 amps. See picture.
Thanks!
I would need a better description of what you are doing to venture a resolution.
Can you post a picture of one of the CTs showing the model please?
I don’t know what a 3.5 splitter is. Do you mean 3.5mm jacks? You say you are measuring “both legs” and have a “couple” of heat pumps. Are you combining 4 CTs into one input?
Are these mini-splits two wire or three wire? Most are two-wire. What happens if you measure only one of the legs?
Big question: Are you sure you have split-phase? True split phase would be 240V. Two phases of a three-phase source is 208V.
Are you sure all of the CTs are in phase? The CTs on different phases must be physically reversed.
Do the mini-splits have pan heaters? That would account for power when they appear to be off.
The power factor indicated in the above picture is very suspect. Mini-splits are usually inverter and operate at much higher PF. If the standby power is pan heaters, I would expect the PF to be near one.
Thanks for replying!
I would need a better description of what you are doing to venture a resolution.
Can you post a picture of one of the CTs showing the model please?
Are these mini-splits two wire or three wire? Most are two-wire. What happens if you measure only one of the legs?
Are you sure all of the CTs are in phase? The CTs on different phases must be physically reversed.
See attached Picture to answer above questions.
I don’t know what a 3.5 splitter is. Do you mean 3.5mm jacks? You say you are measuring “both legs” and have a “couple” of heat pumps. Are you combining 4 CTs into one input?
Two CT’s into one input on the Iotawatt
Big question: Are you sure you have split-phase? True split phase would be 240V. Two phases of a three-phase source is 208V.
Yes-240V
Do the mini-splits have pan heaters? That would account for power when they appear to be off.
Yes, heaters.
The power factor indicated in the above picture is very suspect. Mini-splits are usually inverter and operate at much higher PF. If the standby power is pan heaters, I would expect the PF to be near one.
My concern is I don’t have something hooked up correctly because of the low PF and AMPS are always 2 higher than what calculating watts/volts=amps
I’m going to further investigate this weekend, maybe one or both CT’s are bad. (maybe they were connected without load?)
Watts/Volts does not equal Amps.
Try
Watts / (Volts x PF) = Amps
So I wasn’t taking into account the PF. That explains the amp reading I’m getting. I just need to figure out why these high efficient inverter units are such low PF. Thanks!
I know this is outside the support for the Iotawatt but any suggestions on finding the reason the PF is so low? Wiring or connections cause low pf? Or would it be the design of the unit? Anyone want to chime in on this?
I doubt that 233 Watts is normal operation. Are there any other breakers in that sub-panel? If so, what happens if you turn them off?
What happens if you turn off all breakers in the subpanel except one of the heat pumps, and then the other?
What is the PF when the things are actually running?
The two mini splits are the only items in the sub panel. I raised the temperature and forced one of the units to heat the room up and watts climbed to 2700 with a pf of 93 so I guess there is no issue. Thanks.