I am running a PID controller in front of a laboratory hotplate, I got the hotplate on the very cheap because the thermostat's out.
(Now the thermostat is completely out).
I drilled a hole in the plate the same diameter as the thermocouple, got a snug fit.
I set the PID at 450F to preheat, molds, pit a moldon the plate and started checking the temp with a laser thermometer.
up to 250F the reading on the PID and the laser thermo match each other, but at 450F indicated on the PID I am getting 350F on the laser thermo.
Anyone got any ideas?