Poly-Phase Calibration

The calibration is performed by means of the CAL_T (phases A, B and C), CAL_TN (phases A, B, C and Neutral) or of the CAL_A (phase A), CAL_B (phase B), CAL_C (phase C) or CAL_N (Neutral) commands. To properly calculate the phase calibration constants, it is advisable to set the WECO to apply a noticeable phase difference between the voltage and the current vectors. The recommended value is 60º (power factor 0.5L).

Remember to send a CNF command before sending the CAL command.

The parameters of the configuration command are the voltage, current and angle applied (only current and angle for Neutral). When the command is sent, the application code computes and saves the calibration constants in non-volatile memory.

As explained, user can calibrate the three phases and Neutral individually:

>CAL_A (Ua=220.00,Ia=1.00,Aa=60.00)
Calibrating...
Calibrating Done!
>CAL_B (Ub=220.00,Ib=1.00,Ab=60.00)
Calibrating...
Calibrating Done!
>CAL_C (Uc=220.00,Ic=1.00,Ac=60.00)
Calibrating...
Calibrating Done!
>CAL_N (In=1.00,An=60.00)
Calibrating...
Calibrating Done!
>

All the phases simultaneously:

>CAL_T (Ua=220.00,Ia=1.00,Aa=60.00,Ub=220.00,Ib=1.00,Ab=60.00,Uc=220.00,Ic=1.00,Ac=60.00)
Calibrating...
Calibrating Done!
>

Or all the phases and Neutral simultaneously:

>CAL_TN (Ua=220.00,Ia=1.00,Aa=60.00,Ub=220.00,Ib=1.00,Ab=60.00,Uc=220.00,Ic=1.00,Ac=60.00,In=1.00,An=60.00)
Calibrating...
Calibrating Done!
>

When the process is finished, use the PAR command, as explained in the previous section, to read the measurements and check the accuracy obtained with the calibration.