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Hello Tyrone,

As far as I know, this general system has been successfully used on your supply system (though whether in USA or Canada I can't remember now). You'll obviously need to recalculate the various fiddle factors for 120 V, and of course if you use a voltage monitor, that will need to be 120 V also. As far as I know, there is no problem with running at 60 Hz. But please remember this is a UK site and we tend to assume 240 V 50 Hz, so bear that in mind. I think there's enough explanation in the 'Building Blocks'  section of this website, but don't be afraid to ask if anything is unclear.

The standard emonTx handles 3 c.t's. One user has recently posted about a 3-phase system with 3 stacked emonTx's (9 c.t's in total, though I think his design could be simplified to single phase).

One slight complication that you might need to think about: is your supply what I would describe as 2-phase, i.e. centre tapped 120 - 0 - 120 V?  If it is, then you need to take that into account. A search of the forums should throw up a discussion about that - about March this year I think it was.

Thanks for the prompt response Robert!

I'll order the hardware right now and get ready for quite an adventure... :)

I'll spend some more time on the forums reading as much as I can while I wait for the hardware.

Thanks again.

Hey, I just put together a system here in Maui, using 2 CT's on the two phases coming into my North American style two phase electrical panel.  Just had to setup a special feed in emoncms to add the two power readings together, so far so good!  I used a 120 to 9 V adapter from Digikey, and skipped the rf stuff - I just have an Arduino with some perfboard for the CT analog input circuitry, and an old eeepc collecting the data directly from the Arduino via USB.

So far so good, only problem is the public dashboard on Emoncms isn't working, but I hope to figure that one out soon.

Let me know if you have any q's.

Wade