Thermostat with ±0.5μ K monitoring sensitivity

Publisher Website
Google Scholar
Abstract
A new development in temperature control is presented. This consists in using a Wheatstone bridge in a proportional thermostat both as a monitoring and a heating unit. The sensor is a copper wire closely and evenly wound around the volume to be temperature controlled. The other bridge resistors are manganin wires and are wound around the same volume. The theoretical limit of control is 0.5 mu K or 1 part in 109 of the sensor resistance. In practice the stability of the resistors and the design of the thermal system limited somewhat the temperature stability. Tests at 25 and 37 degrees C operating temperatures showed a 15 mu K/day long term drift, including the drift of the relatively modest system used to measure the temperature.

This publication has 8 references indexed in Scilit: