GE Rx7i CPU shuts down due to overheat of CPU

We are using GE Rx7i PLC, recently installed. Last week one of the PLCs quit by it self and shut our plant down and it cost at least 4 hrs downtime. When we looked at the CPU, it was boiling hot.



I am thinking to put some kind of overheat alarm to the operator station to prevent this overheating issue, (eg. if the cpu's temperature goes above x amount give an alarm to the station or something), which will give us some time cool it down before the cpu quit. I do not know the best way, I am thinking what is more feasible. I can do either a soft alarm or a hard wired alarm, I may need to get a heat sensor, if so what is the best kind.



Just give me some advice or any better way to solve this problem. Your help is really appreciated.

Thanks,

Andrew

Check with your distributor, there is a fan kit available for the RX7i.
Is the cabinet Air Conditioned? Do you have proper clearance above and below the CPU rack?
There is also at least one internal (%S??) bit that will give you an over temperature alarm. You can look it up in Proficy ME.

Thanks for your comments.
I looked at the internal bit for the over temp alarm, but

it will work only when the operating temperature (32-140F) of the CPU exceeds the normal operating temp, and this will be too late to respond/trouble shoot and it may still kill the plc.​

I am trying to do something alert me early enough to react. I may put some kind of thermostat to sense the preset heat and input to plc and output to an alarm. welcome any comments.​

​

thanks​

I looked at the internal bit for the over temp alarm, but

it will work only when the operating temperature (32-140F) of the CPU exceeds the normal operating temp, and this will be too late to respond/trouble shoot and it may still kill the plc.​

I am trying to do something alert me early enough to react. I may put some kind of thermostat to sense the preset heat and input to plc and output to an alarm. welcome any comments.​

thanks​