Hi engineers,
I currently have a high-temperature DIN25 paddlewheel flow meter in my machine. This flow meter uses a non-galvanic isolated supply which means I read the 4-20mA from the instrument. The flow meter builds up with a paddlewheel flow meter and an electronic board (frequency to current) converting to a 4-20mA signal. The flow meter also complies with EMC standards of EN61000-4-3, EN61000-4-4 & EN61000-4-6. The issue is that the flow meter reading will be abnormal (more than 22mA) when the 45kW VFD is running. I also have instruments such as PT probes and pressure sensors in the machine that do not have abnormal readings during VFD running. All the instruments, flow meter, PT probe and pressure sensor, installation radius 3-4 meters from the VFD. Thus, does the VFD create noise and affect the paddlewheel sensor? The flow meter supplier keeps explaining the noise problem but does not in detail. I need some experts who also face this similar issue and share some knowledge.
Thank you so much for your attention and participation.
Cheers
Eddy Kee