The Model 321 is a microcontroller based autotuning temperature controller which provides a simple, low cost answer to basic control needs.
Differential input allows four-lead measurement of the sensor signal.
Precision thermometry is the most basic building block of any digital controller and is necessary for stable, accurate control. Careful analog design provides the Model 321 with stable and repeatable measurements. Control parameters can be entered manually or by the autotuning algorithm. Two heater ranges, with the high providing 25 watts and the low 2.5 watts, allow for a variety of cryogenic cooling systems. The power output of the Model 321 is a quiet, variable DC current to ensure as little noise coupling as possible between the heater and experiment.