The function of this temperature reference unit differs from other rack-mounted systems, because the temperature of the metal block in which the thermocouple and copper leads are inserted actually varies with ambient temperature. A separate output signal is produced, which is proportional to the difference between the environmental temperature and the actual reference temperature. The output signal can be fed directly into a computer/data logger to give accurate compensation over a large ambient range.
A thermal reservoir, heavily insulated within the thermocouple reference, contains the reference junction probes.
The reservoir temperature slowly follows the ambient temperature; an electrical compensation device is thermally integrated with the reservoir and thus senses the reservoir temperature.
The thermocouple reference produces an output proportional to the difference between the reservoir temperature and the reference temperature (usually 0°C). This is the signal the computer/data logger uses to compensate for the temperature of the reference probes junctions.
The output can be in the form of a DC mV output, 4-20 mA, or from a platinum resistance thermometer.
Please discuss this thermocouple mount with us prior to order.