A
we have a sensotech pressure sensor to measure refrigerant pressure. this is connected to a compressor. the compressor is driven by a motor connected to a freq drive to vary the speed. initially when the compressor is not running the pressure indicates 7 bar. the moment the drive is switched ON the pressure value drops to 4 bar when actually the pressure should be the same. the sensor is a three wire sensor giving 4-20mA output. this is connected to a eurotherm AI module. can anyone suggest checkpoints to resolve this problem?