Emerson Exchange 365

• Not Answered

We have a communication loss when moving Rockwell E300 Overload Relay from a PK750 controller to a PK300 controller. Why?

We added some PK300 controllers to our version 14 DeltaV system. We then moved the logic and interface for a Rockwell E300 overload relay from a PK750 controller to a PK300 controller. After the move, we loose communication with the overload relay. There are other VFD's that were moved and are communicating with the new PK300 controller.

I tried moving the interface from the PK300 back to the PK750 controller, and the communication shows good now. Why?

Is there something we need to do to get the PK300 to communicate with the E300 overload relay? Can the PK300 controller communicate with the E300 overload relay.

See the attached images.

Cornell

• 19 Apr 2021 10:25 PM
• Cancel

1 Reply

• Andre Dicaire

  

  • 19 Apr 2021 11:21 PM

  The PK300 and PK750 have the same capabilities, other than the allowed IO count and number of Ethernet devices. You show 19 devices in one controller and 10 in the other, so you are good on number of devices. (PK300 supports 32 devices, PK750 supports 64 devices)
  
  Did you cycle power on the E300 after you moved the configuration to the PK300? The E300 supports one master. Once it recognized the PK750 and connected it would reject any other master requests. Although the PK750 may no longer sending commands, if the PK750 remained connected and available, the E300 may not have dropped it as its master. I'm assuming you downloaded the PK750 port to remove the E300 in question. If you didn't, then it certainly was holding the attention of the E300.
  
  if it works with the PK750, it will work with the PK300, barring any configuration or network issues.

  Andre Dicaire

  • Cancel