Internal temperature of AB PLC5

I'm worried about our PLC cabinets getting too hot and possibly causing problems with the processor and want to log the temperatures over time.

Is there a tag in PLC5 that shows the ambient or processor temperature?

No there is not, what is the temperature in the cabinet?

I'm not sure exactly.

It gets over 110 degrees in summer on the floor and much hotter in the controls cabinet.
Some have fan cooling, but this is just pumping in more hot air.

If you have instrument or mill air available try Vortec Coolers. We use them to cool electrical I/O enclosures in our Power Houses, Lime Kiln and Kraft Pulp Mill. They work very well.

PLC5's are rated for 140 Deg F....I imagine other components will start failing before the PLC5 does. Not a fan of fans as they blow more dust into the cabinet than anything, and noone maintains filters. Heat Exchangers are better for air quality, but still require external filters to be changed for max efficiency...But do a better job of keeping out dust. A small cabinet air conditioner w/ thermostat is your best bet for 110 deg, which in relative terms, isn't that hot.