measuring doubled amps on unbalanced 240 loads with two CT
Posted: Fri Feb 21, 2020 10:02 pm
Last week My GEM/Dashbox began report a sudden increase of power comsumption by my heatpump/AC condensor previously it reported typical usage of about 850-900watts and 7-8 amps. Then just 40 minutes later it start reporting 1600-1800watts and 14-15amps.
When it goes into defrost mode the fan turns off and only the compressor runs. It used to drop to 600-650 watts and 5-6amps. Now it is 900-1300watts and 9-12amps.
The Condensor is a 2.5ton unit with a compressor Rated Load Amps of 14.1amp and a fan Full Load Amps of .5amp
Amps measured at the condensor with a clamp meter is 6.6 on one leg and 6.8 on the other. Just the compressor motor is about 5amps
I have CTon both legs running the condensor.
After typing all this out I pulled one of the CT leads out of the GEM channel terminal and the reading whent back to what they were before. I decided there was a CT wire not making contact in the GEM terminal and that it got bumped to make contact when I took the cover off to the GEM last week to see how many channels were left to add another monitored circuit. I have a whole year of incorrect data for the HVAC condensor.
Now though it has brought to my attention that before it used to report the correct amps but the watts was incorrect, now the watts are about right and the amps are double. My other unbalanced 240 circuits(oven range, dryer) have this same problem with the amps. My dryer shows about 4900watts and 41amps. What is the setting to correct the amps when both leads are monitored on a 240v circuit?
When it goes into defrost mode the fan turns off and only the compressor runs. It used to drop to 600-650 watts and 5-6amps. Now it is 900-1300watts and 9-12amps.
The Condensor is a 2.5ton unit with a compressor Rated Load Amps of 14.1amp and a fan Full Load Amps of .5amp
Amps measured at the condensor with a clamp meter is 6.6 on one leg and 6.8 on the other. Just the compressor motor is about 5amps
I have CTon both legs running the condensor.
After typing all this out I pulled one of the CT leads out of the GEM channel terminal and the reading whent back to what they were before. I decided there was a CT wire not making contact in the GEM terminal and that it got bumped to make contact when I took the cover off to the GEM last week to see how many channels were left to add another monitored circuit. I have a whole year of incorrect data for the HVAC condensor.
Now though it has brought to my attention that before it used to report the correct amps but the watts was incorrect, now the watts are about right and the amps are double. My other unbalanced 240 circuits(oven range, dryer) have this same problem with the amps. My dryer shows about 4900watts and 41amps. What is the setting to correct the amps when both leads are monitored on a 240v circuit?