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Everything posted by PaulK

  1. Hi Aus, thanks for the support. Yes, when the coil is de-energized, a short time after (instant to 10 minutes) the PLC goes "Roy Munson" (that is a Kingpin movie reference). Correct, this panel was designed and built without regard to best practices, standards, noise, guidelines, solar flares or silk underwear. I have been doing software exclusively for a while (how the cards were dealt), and I know a tiny bit about electrical from just working in this field for 25 years. I can not count all of the things I would have done differently in this panel...some of it is just common sense. Thanks again, I will update when I have more feedback.
  2. We are going to try Diodes on each solenoid valve, across the Coil, reverse bias. From reading on the interwebs, it would appear the 1N4004 is the go to diode. I will report back.
  3. Hello - So the noise is coming from a 24VDC valve solenoid coil. The coil is being energized directly off of the Snap IO output (I didn't design this). Question - I am not an electronics type, more software. So options... Opto Relay? Solid State Relay? Diode Snubber Circuit? I would like to test with a Diode, has anyone used this method, and if you did, which type of diode was selected? Thank you! Paul p.s. - I am sick to my stomach over this. Work, make mistakes and learn,
  4. Thanks Flex727 - no, I didn't add any tape or screw it down. I rerouted some IO away from 575 and motor leads, after doing that the results were dramatic, I went from a fault every 15 minutes to one fault after 14 days. I am ordering a new Snap IO Module and V570, was talking to Micheal from Unitronics just now, and the thought was that the unit could be degraded from all the previous noise exposure. It is probably a long shot, but something we are going to do. I am also going to be probing for noise as well at checking all grounding. One last item to try was to float the 24VDC power supply from earth ground. With the new unit, I will tape where I can to keep the Snap IO fixed to the V570. The current snap IO module is very secure and snug with the V570, but I will try what you recommend. Problem is, if it is only happening every two weeks, and I change more than one thing at a time, then I will not know with certainty what corrected this issue.
  5. Well, it is back after 14 days of running. The PLC/HMI starts to beep slowly and then Black Screens. Unitronics tech support is suggesting OS is corrupted? Is it possible unit has been degraded? I am considering replacing the V570 as well as the Snap IO board.
  6. I want to thank everyone who responded... Thank you! I fixed the issue within 90 minutes. The digital IO to and from the drive (Run Command and Drive Faulted) were tie-wrapped to the 575 VFD Line Supply. They had installed Line Reactor beside the 24 VDC power supply (yes, un-shielded motor leads up and out of the control panel) Shields on twisted pair cabled had been snipped off, so there was no drain connection to ground. I ran new digital IO wired and connected the drains at one end to ground The new digital IO wired crossed the 575 at 90 degrees, and I made sure the IO was spaced away from the 575 and the motor leads I removed the Line Reactor Problem solved...I hope. The system has been running for 48 hours, previous to this it would only stay up for 15 minutes...looks promising. This was not following wiring fundamentals 101. Best regards, Paul
  7. Hello, Going to start troubleshooting tomorrow morning. One more piece of information. Before the stop error, V570 starts beeping before it faults out. Going to check grounding and cable routing and probe for noise.
  8. I have been talking to our local Uni dealer. He gave me some varistors to try, also some 120ohm and .1uF caps. Of course I will try to eliminate at the source, but if I can't has anyone added these types of noise filters to the Snap IO points? I will post some noise pics next week! Hope everyone has a nice weekend!
  9. Also, apparently the Stop Error happens several minutes after the VFD/Motor is running, which would lean towards vibration?
  10. I was actually looking at adding the 4 holes in the snap IO (yes...void the warranty) and add some self tapers to hold the IO snug. Thanks Flex727
  11. We only get the Stop Error when the Grundfos VFD starts, so I am 99.9% sure this is VFD noise causing the Stop Error. I am not exactly sure where they ran the expansion cable, but I will find out on Monday when I get to site. If it is running anywhere new VFD or power cables I will space it out. I have a fuke 125B scope, so I will be probing for noise on all the snap IO and basically all the connections to the 570. I hate plastic enclosures as well, they have no place here, again, cards I was dealt. I will post some more pictures.... Yes, Weg motor is VFD rated, 0 turn down.
  12. Thanks so much Joe. I am going to site with a Fluke on Monday. I am also going to Sayal to pick up some 0.1uF caps. So basically put the cap between each digital IO point and ground if I see noise on those wires? I also am using some analog...and suggestions for that? THanks again Joe!!!
  13. Thanks for taking the time to reply Aus! The PLC is in its own Enclosure. The VFD is a Grundfos/Danfoss IP67 Skid mounted unit outside the control panel. Please see attached picture. I do not like plastic enclosures, but these are the cards I was dealt.
  14. Complete Part number... V570-57-T20B-J PLC + HMI V200-18-E6B Snap in IO Module S8VK-G12024 Omron Power Supply 100-240 V AC/ 24V 5A 120 W Output EXL-CAB295 Unitronics Expansion Cable 2.95 Mts EX-D16A3-R08 Expansion Module
  15. Thank you Flex727, I will follow your suggestions. I should add, that after this happens, power cycke, and V570 operates normally until the second VFD is started again. Could be vibration, will check that. IS there a good source on where to add snubber or zener diodes to the IO into the snap?
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