Current transformer & power calculation questions

I have 3 x AT 50 B10 current transformers (CT), one on each phase (240V RMS), Vp, going into a CNC machine.

The output of each is 0-10V where each volt corresponds to 5A RMS passing through the CT.

I want to calculate power over a given time period, t0 to tn, for each phase (P1, P2, P3) & for all phases added together (PT).

My thoughts on how I do this,

Covert my acquired voltage to current, Ia = Va x 5

Sum Vp x Ia over t0 to tn for each phase

Then PT = P1 + P2 + P3

This is RMS power?

Is it that simple? Am I missing something here? Have I actually calculated electrical energy use here?

• Rms power does not exist per se. If you multiply the two rms values of current and voltage, you obtain apparent power, expressed in VA. If you want to compute power in watts - the power that performs the work in the physical sense - you first plot the instantaneous power $p(t)=i(t)v(t)$ then average it across a line cycle: you obtain watts. Commented Aug 3, 2023 at 11:36
• @VerbalKint " average it across a line cycle" what do you mean by line cycle? Commented Aug 3, 2023 at 12:41
• A line cycle is one complete sine wave period. Commented Aug 3, 2023 at 14:25
• Oui, a complete mains cycle period, merci Aaron : ) Commented Aug 3, 2023 at 14:54