Frequency of the line voltage
fundamental harmonic component is determined by the Metrology module and provided in
the variable FREQ. A separate frequency is determined for each individual voltage
phase, for each of three phases, x = [A, B, C].Note: Maximum accuracy in frequency measurement is achieved at the end of the
integration period. Therefore, the register should be read immediately after the
integration interrupt is generated. However, since this register is updated each
time a positive zero-crossing in the voltage line is detected, it is possible to
read the register after the full cycle interrupt, enabling a faster refresh of
the value.
