Hi Suman, To confirm, you are getting pulses for higher currents? For low currents, do the pulses slow down, show up randomly, or not at all? What voltage and current ranges (min, max) are you working with here? What values were used during your calibration? Depending on how low your currents are, they may be lower than what's specified by the RESIDUAL_POWER_CUTOFF macro definition and could be ignored. This macro appears to be set to 2.5W by default (using a value of 250), according to Section 4.4 in the Implementation of a Three-Phase Electronic Watt-Hour Meter Using the MSP430F471xx app note. I'd suggest lowering this value according to your application. In conjunction with this change, it'd also be good to increase your PHASE_ENERGY_PULSES_PER_KW_HOUR macro to 6400 pulses per kWh from 1600. Another important macro is the ENERGY_PULSE_DURATION macro. Here, if the duration of LED on-time is too large, you could experience overlap at higher currents where the pulses merge into a continuously high signal. Since you're working with low currents here, this probably isn't the issue, but I still wanted to point it out. Regards, James MSP Customer Applications
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