A customer has asked me to look into a problem they are having with a Honeywell PLC system. Apparently the i/o seems to stop responding for anything up-to 1/2 hour, but it seems the CUP continues processing. Does anyone have any experience with this type of PLC. Configuration is: 3 PLC racks 1 CPU LCS-9010-036 6 digital input modules 621-3580 3 digital output modules 621-6575-R 5 analogue input modules 621-0020-R 6 analogue output modules 621-0010-AR 4 RTD input modules 621-0025R 3 Power supplies 621-9933 2 Parallel I/O modules 621-9937 1 Ethernet Module 620-0073 Any advice greatly appreciated regards, Phil McKay TRESCO INTERNATIONAL (AUST) PTY LTD Silvan, Vic, Australia [email protected]

 

Phil, I am doing now a project with S9100E plc's. I had a problem that from time to time the communiction to the HMI freezed (but the I/O was OK). I upgraded the Ethernet card to ver 1.6 (by replacing 3 eproms) and the problem no longer exist. I hope that will help you Moti

 

We have a lot of experience with the Honeywell S9000 family. Can you give me more details? Are they using Scan as the HMI? What is actually stopping? We have 22 servers with probably 100 plus S9100e (big brother to the S9000) scattered around our research facility. I think we can help once we know more. Rodney Park UOP Automatio Group Leader [email protected]

 

Thanks to those who responded I haven't actually seen this system as it is about 1000Km away, so I'm trying to fault find remotely. I may eventually end up having to visit the site. The HMI is "Plant Scape" The thing that is actually stopping: seems to be the scanning of the digital inputs It happens something like this: An operator pushes a button to stop a pump (physical button - wired to input module) - the pump does not stop, tries other buttons - nothing is responding - some time later (up to 1/2 hour) the pump stops Last year an engineer at the site added a watchdog pulse to the last input of each input card. The pulses are from an external timer (5 sec on, 5 sec off) PLC timers are programmed to monitor these pulses The PLC shuts down the process if it times-out. - this works - the process now stops if the inputs freeze-up - so it seems that the digital outputs are working ok, even when the inputs freeze-up Apparently they have tried replacing I/O modules & system PSUs They haven't replaced the CPU - I have requested they replace the CPU. - this is being done this weekend, will advise of the results regards Phil