bhedding024
Member
Working on an incremental upgrade of existing SLC 500's and Panelview 550's over DH-485, to ComapctLogix and PVP 7's over ethernet. My test setup is a SLC 500 rack with a 5/05 (OS501). Channel 1 is DH-485 connected to a 1761 NET-AIC. Channel 0 is ethernet. The PV 550 (2711-K5A2) is connected to DH-485 via 1747-AIC. The CompactLogix (1769-L16ER-BB1B) and PVP 7 (2711P-T7C21D8S) are both connected to the ethernet network.
I can set up a message in the CompactLogix to write values input via the PVP 7 to an address in the 5/05. However, if I manually change the value in the 5/05, the value is overwritten by the existing message. Do I only want to send the message on a change of data and otherwise just read? Set up a read / write flip-flop? My problem is figuring a way to read and write from either PLC / HMI system. Maybe there is an easier way, I don't know. Any thoughts or advice on a different approach would be appreciated. Thanks.
I can set up a message in the CompactLogix to write values input via the PVP 7 to an address in the 5/05. However, if I manually change the value in the 5/05, the value is overwritten by the existing message. Do I only want to send the message on a change of data and otherwise just read? Set up a read / write flip-flop? My problem is figuring a way to read and write from either PLC / HMI system. Maybe there is an easier way, I don't know. Any thoughts or advice on a different approach would be appreciated. Thanks.