I have omron PLC type as cpm2c.I have problem with it.sometimes plc goes to stop and occur I/O bus error in plc.I use cx-programmer software.can anybody help me how can I solve this problem.
thanks
possible causes are communication losses to your other devices the CX_programmer should report which device is dropping out if its on a backplane Omron has some unreliability on the backplanes but if its on communication cables one could be faulty. What exactly do you mena when you say the PLC goes to stop? when you disconnect power to it??
when I say plc goes to stop run led on plc unlit and alarm led lit.
ann when i connect to plc in cx-programmer alarm logs I/O bus error massage occur.this problem happens sometimes when I power off after 5 minute plc go to run mode and plc work correctly but after 5 or 6 hours plc go to stop again.and when power off and after 5 minute on plc go to run mode.when I power on after power off without delay plc doesnot go to run mode.I have to wait some minutes
this problem happens sometimes when I power off after 5 minute plc go to run mode and plc work correctly but after 5 or 6 hours plc go to stop again.and when power off and after 5 minute on plc go to run mode.when I power on after power off without delay plc doesnot go to run mode.I have to wait some minutes
IMHO, this definately sounds like an over heating problem. I agree with Mordred. Are the expansion modules warm? What type of environment is this unit in? Have you tried to reseat any modules on the backplane? Post what you have already tried to do to fix the problem or investigate it. Might help us eleminate some issues.
The envirement that plc works is an electrical cabinet in chemistry laboratory.there is not warm and any unit is not warm.at first I think this problem occured from poor connection in backplane bus. I opened all modules and fixed them and assemeled again.but this problem wasnot solved.I think there is problem in cpu module is it possible?
regard
The envirement that plc works is an electrical cabinet in chemistry laboratory.there is not warm and any unit is not warm.at first I think this problem occured from poor connection in backplane bus. I opened all modules and fixed them and assemeled again.but this problem wasnot solved.I think there is problem in cpu module is it possible?
regard
Anything is possible. Do you have spare parts available? If yes try firstswapping out the backplane. If no result, change out the power supply and so on. Maybe someone with better suggestions will come along but until then check on available parts so that you can continue to move forward towards a solution.
I gather you need to wait several minutes before you can resart the PLC after it shuts down? if so then I agree with BobB on sending the unit to Omron and replacing it if so then it does sound like overheating on the CPU itself. If you have a temperature gun try seeing if their is any rise in temperature
I see what your saying BOBC after looking the type of connections and units involved try replacing the power supply module first also make sure you've got solid connections between the expansion units one other remote possibility is that the chemical fumes in the lab may be causing extra corrosion on the connection pins creating a high resistance I would try cleaning all the pins between modules. Also inspect the traces if you can get to them some chemical fumes can break down the epoxy coating and traces will usually show some form of discoloration
tomorrow I clean the back plane connectin.If I get result it is good if not I try some other checks.I thank for your good suggestion for fixing this problem but I want you do not take me alone and I always looking forward to hearing you.
Best regards