In one of my application, I want to heat PT100 RTD element at the controlled temperature.
Which method should I use to heat the RTD element? Controlling will be done with any microcontroller unit.
Start with the voltage and current relationship and the tables for PT 100 plus temperature coefficient from your specs, and you have your answer at hand,
>In one of my application, I want to heat PT100 RTD element
>at the controlled temperature.
After taking a bit to re-examine your question, if you are monitoring a heated oven or part with a PT 100, you still need the temperature coefficient for your particular sensor, but is your controller is adjusting the heat input to your system?
If so, when the temperature exceeds your desired temperature (your setpoint), you lower or turn off the heat source.
If proportional control, the amount of adjustment is based on the delta T from setpoint. Some systems add dynamic compensation to speed up the heating, others proportional only adjustments that is system dependent.
You can use whatever you can think of to heat the RTD. Some examples would be electric heat element or gas burner element. In the electric heat element option, the output or manipulated variable would be connected to a relay which controls the flow of electricity to the element and the controller would be configured as on/off PID control (the output would be turned on an off to give the same regulating effect as normal PID control. Most 'Hot Box' Calibrators work on this principal.