Temperature is the most important common measurement. Temperature determines product formation rate and yield in reaction and crystallization processes and product composition in separation processes. Temperature is also important for monitoring energy balances and heat transfer coefficients.
Temperature loops benefit more than most loops from the use of derivative action. The rate time can be 1/2 of the total loop deadtime or larger by the use of a wireless smart transmitter, the enhanced PID for wireless, and a proper installation location and thermowell design.