Setting to monitor double breaker leads

[dotJake]

My panel like most has some higher AMP breakers that are linked/bridged across two panel slots. My AC, for example, has two 40A breakers linked. Does that mean I need to CT each lead with a 50 and put both leads into one port, or CT both leads with a 100 and use one port? The panel is 200A service.

Thanks.

[Teken]

My panel like most has some higher AMP breakers that are linked/bridged across two panel slots. My AC, for example, has two 40A breakers linked. Does that mean I need to CT each lead with a 50 and put both leads into one port, or CT both leads with a 100 and use one port? The panel is 200A service.

Thanks.

If the 240 circuit does NOT have a neutral you can use one or two CT's it comes down preference.

If using one CT you will simply go into the GEM's setup page and enable the software doubling feature. If you want to measure both electrical legs because you want complete accuracy then that is another method.

Some people use one CT due to cost vs others want to know exactly how that device is operating etc. Even though in a ideal world a 240 balanced load should pull the same power it doesn't always.

If a 240 load has a neutral you must use 2 CT's to capture the power readings. Most AC units have one 120 feed to power the fan vs the compressor. A stove needs to two CT's in most cases because the top (convenience) outlet is obviously 120 VAC.

[dotJake]

Ahh I see. I will pop the breaker cover off and see what I have to work with. I keep trying to do this with a single 1240 but when I logically group them I am into another 1240.

[Teken]

Ahh I see. I will pop the breaker cover off and see what I have to work with. I keep trying to do this with a single 1240 but when I logically group them I am into another 1240.

My apologies I thought you were using a GEM and not a ECM-1240. Please ignore any reference to the software doubling feature OK.

All other comments with respect to monitoring the 240 load with and with out a neutral is valid though.

[ben]

Ahh I see. I will pop the breaker cover off and see what I have to work with. I keep trying to do this with a single 1240 but when I logically group them I am into another 1240.

Once you approach using an ECM-1240 duo package, its worth considering a GEM package for the extra ~$50. 1 GEM would cover everything and leave you with some channels left over in case of future expansion.

I've somewhat recently updated http://www.mypowerpanel.com/ to include more information, under the Product section, there's a table at the bottom that compares the two products (http://www.mypowerpanel.com/products/#compare).