Hi,
I’m trying to find the correct calibration values to get accurate readings. I followed Roberts advise in the 3-phase firmware.
Is it correct that Phasecal1
can be between 0 and 2 but Phasecal2 and Phasecal3
should be between 0 and 1? What happens if I can’t find a combination for PHASE3
and Phasecal3
in this range? Can Phasecal
also be negative?
My best combination is:
#define PHASE2 7
#define PHASE3 14
double Phasecal1 = 1.20;
double Phasecal2 = 0.40;
double Phasecal3 = -0.30;
I don’t use CT4 and I send some extra values via RFM69 like current and power factor and I’m using the jeelink-library (see this topic for the reason: 3-Phase with ACK)
Using a resistive load on all three phases with 1 ampere I get the following values:
Voltage: 237.90
Phase 1: 0.99997 A, 239.27 W, 237.89 VA, PF=1.006
Phase 2: 1.00427 A, 240.02 W, 238.91 VA, PF=1.005
Phase 3: 0.99452 A, 241.08 W, 236.59 VA, PF=1.019
Putting all three clamps around phase1 gives me this:
Voltage: 238.11
Phase 1: 1.01397 A, 242.99 W, 241.43 VA, PF=1.006
Phase 2: 1.01108 A, -121.43 W, 240.75 VA, PF=-0.504
Phase 3: 1.00552 A, -131.86 W, 239.42 VA, PF=-0.551
It seems quite good to me, but I’m concerned it is not, because of leaving the calibration range.