adccommunitymod (AutomationDirect) asked a question.
P2000 hsi
Created Date: September 11,2017
Created By: whitejw
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We recently put an HSI module on a P2000. Have an encoder that is just a 24 volt pulse. We seem to have an extreme noise problem on this module. Just about any motor running within 50 ft of the unit causes the count to count up at a rapid rate, several thousand in just a few seconds. We have changed encoders, changed cables, grounded, ungrounded, shielded, unshielded, rerouted cables, etc. Nothing seems to work. Is this an issue with this module?
Created Date: September 11,2017
Created by: whitejw
We recently put an HSI module on a P2000. Have an encoder that is just a 24 volt pulse. We seem to have an extreme noise problem on this module. Just about any motor running within 50 ft of the unit causes the count to count up at a rapid rate, several thousand in just a few seconds. We have changed encoders, changed cables, grounded, ungrounded, shielded, unshielded, rerouted cables, etc. Nothing seems to work. Is this an issue with this module?
Created Date: September 11,2017
Created by: MikeN
How long is the wires between the encoder and the module?
What encoder are you using?
If the motor on a VFD and is the VFD in the same enclosure as the P2k?
Created Date: September 11,2017
Created by: whitejw
It's about a 15 ft wire run from encoder to module. It is shielded cable and in a separate conduit.
The encoder is a Encoder Products Co, Accu-coder, Model 711.
Some of the motors are on VFD's. Not in same cabinet.
Created Date: September 11,2017
Created by: MikeN
Try unscrewing the cable from the encoder, but leave the cable where it is. If you turn a motor on does it still count up really fast?
If not, then the problem is probably somewhere in the encoder and the connection to the machine. Possibly too much vibration or something.
If you do still have the problem, pull the cable back through the conduit but leave it connected to the HSI. Just leave the bundle of wire over by the cabinet. If you turn a motor on now, does it still count up?
If not, then you have narrowed the problem down to the run itself. Which could mean interference from the motor magnetic field coupling with the encoder wiring, not some issue with the conduit.
Created Date: September 15,2017
Created by: GlennLee
Ensure that the power to the encoder isn't noisy or shared with a noisy load. Is the common for the encoder power tied to the common of the HSI?