View Full Version : Negative frequency + sound like old radio.

07-06-2023, 10:17 PM
Hi for everyone
after big boom on the first VFD.
I'm trying to marry the New vfd with same characteristics ( 220 v / 380v 2.2kw CHINT) and the two spindles with no support no information no data sheet....
according to mr google... It's :
2 pole
and I have set the Motor Stator Impedance to 6 homs.
Everything went well
But i noticed two things
1) the display shows negative values
2)strange sounds like an old radio
PS I am a mechanic so electricity is a bit difficult for me.
it is a machine for smoothing the edges of wooden plates.
it's my brother's machine...i appreciate your help and sorry for my bad English [emoji120][emoji120][emoji120]


Envoyé de mon A1601 en utilisant Tapatalk

24-07-2023, 11:25 AM
When a VFD displays negative values, it often indicates a reverse rotation direction. Reversing the direction is usually a simple adjustment in the VFD's settings.
Now, let's address the strange old radio-like sounds. These peculiar noises can be attributed to electrical noise interference. When a VFD operates, it generates harmonics and electromagnetic interference, which can manifest as audible sounds resembling static from an old radio. Some VFDs have built-in motor filters that can be enabled to reduce noise. Check if your CHINT VFD has this feature and activate it if available.