Yeah that’s possibly a problem. I read a little about that after I got deep into this project.
Some of the things I’d like to monitor are tools in my wood shop. Air compressor motor, large bandsaw (actually, the brake, not the motor, so I should be good there), and dust collector primarily. But, it would be quite nice to see roughly how much it costs to spend 8 hours out there. Oh well, that’s another topic that I haven’t explored real deep yet.
That part is OK. During calibration is when you need a resistive load.
So, if you don’t have a large non-reactive load, pass 20 turns through the CT and use a 100 Watt light bulb.
That’ll give you the same results as if you were using a 2 kW resistive load, e.g. an electric space heater w/o a motor.
If you’re not using the ‘shop’ c.t. and a.c. adapter, your phase_shift = 1.7
will be wrong, and you’ve got the order you did things in wrong. You need to get voltage first, then current or apparent power (i.e. voltage × current) to match, then adjust phase_shift to make real power match (or make real power = apparent power with a resistive load).
As you’re measuring largish motors - yes, but it’s probably not all that critical, as their power factors are likely to be good-ish. Certainly, it’s something I would want to get as close as I could. When it gets really misleading is with small motors with power factors that are really poor (0.5 or worse) and some power supplies that can appear even worse than that.