Hi all,
I had a setup with 2 Micrologix 1100 connected to a Panelview C300 over DH-485. I was mandated to upgrade the HMI, and proposed to install a Panelview 800, which was the direct upgrade of the C300 recommended by Rockwell. Note that pulling new cables is not an option and we had to keep the same wiring.
We converted the C300 program to a PV800 with CCW (exact same communication settings). The HMI was installed and wired, but doesn't communicate with both PLCs. We re-installed the C300 to see if the issue was the wiring (HMI was moved to a new panel) or the configuration, and it didn't communicate anymore... I disconnected the Orange/White pair at the HMI and at the first PLC to do a point-to-point check, and the wiring was ok. I plugged back the pair as it was, and the PLC stopped communicating with the other one... After power cycling both PLCs, it didn't change anything.
I've attached a diagram of the communication wiring and devices. The wiring between PLCs hasn't been touched, and the wiring between the second PLC and the HMI is identical.
I am not familiar with Micrologix and DH-485 protocol... I must be missing something.
Please help.
I had a setup with 2 Micrologix 1100 connected to a Panelview C300 over DH-485. I was mandated to upgrade the HMI, and proposed to install a Panelview 800, which was the direct upgrade of the C300 recommended by Rockwell. Note that pulling new cables is not an option and we had to keep the same wiring.
We converted the C300 program to a PV800 with CCW (exact same communication settings). The HMI was installed and wired, but doesn't communicate with both PLCs. We re-installed the C300 to see if the issue was the wiring (HMI was moved to a new panel) or the configuration, and it didn't communicate anymore... I disconnected the Orange/White pair at the HMI and at the first PLC to do a point-to-point check, and the wiring was ok. I plugged back the pair as it was, and the PLC stopped communicating with the other one... After power cycling both PLCs, it didn't change anything.
I've attached a diagram of the communication wiring and devices. The wiring between PLCs hasn't been touched, and the wiring between the second PLC and the HMI is identical.
I am not familiar with Micrologix and DH-485 protocol... I must be missing something.
Please help.
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