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Lost comms with our controllers, then one controller went through a cold restart, power issues?

Hi,

Could anyone help explain our situation please?

DV-3 is an MX controller, DV-1 and 2 are MD plus controllers, we are running version 13.3. all controllers have power and backup supplies and we run with a UPS.

Our problems started, as you can see on first pic controller_fail_1, with losing coms to our 3 controllers, first DV-3, then DV-1, then DV-2, what followed was lots of switching for all our devices back and forth between our two switches, but only DV-1 and 2 seem to be mentioned, DV-3 isn't mentioned again until much later when it goes through a cold restart, as seen in pic controller_fail_2.

Upon investigation one of the power supplies for DV-3 had tripped, but the primary is still operational, for DV-3 to go through a cold restart doesn't that mean that the controller lost power?

• controller
• ups
• Power

Lee W.

• 27 Jun 2023 10:32 AM
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1 Reply

• Matt Forbis

  

  • 27 Jun 2023 12:23 PM

  The most common cause of a Cold Restart download is a loss of power. If I'm not mistaken, there are some cases where a controller will do a switchover/reboot if it loses communication to all IO and network devices (Maybe someone else will chime in before I get a chance to research it).
  
  In DeltaV Diagnostics, there is a parameter SecsLastPf that will tell you how long it's been since a power fail to confirm this is what happened. The other thing I note in your first screen shot is that DV-1, DV-2 and DV-3 all have some sort of connection issue to each other. This is interesting in that usually you only have a Device Connection Failure after both Primary and Secondary networks fail and/or the controller disappears from the network. Since DV-1 and DV-2 can't talk to one another, I would definitely check on your network health as well.

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