vik1501
New Member
Can somebody provide me with circuit for calculating power factor using standard components ?
I tried to build circuit, but could not measure pf correctly. First the output of voltage and a current transformer were amplified and fed to zero crossing detector ( using LM339).
These zero crossing TTL outputs of LM339 were give to microcontroller and time difference calculated using s/w.
However the circuit behaves erratically for inductive loads. My querries are
1. Is filtering of o/ps of voltage & current transformers arre needed ?
2. If yes , the is there an IC which can do this or shall I design my own low pass filter especially to do with inductive loads which produce high noise on the line and I found that the waveforms are distored
Regards,
I tried to build circuit, but could not measure pf correctly. First the output of voltage and a current transformer were amplified and fed to zero crossing detector ( using LM339).
These zero crossing TTL outputs of LM339 were give to microcontroller and time difference calculated using s/w.
However the circuit behaves erratically for inductive loads. My querries are
1. Is filtering of o/ps of voltage & current transformers arre needed ?
2. If yes , the is there an IC which can do this or shall I design my own low pass filter especially to do with inductive loads which produce high noise on the line and I found that the waveforms are distored
Regards,