Isorac Model 844

 

The function of this reference unit differs from other rack mounted systems in that 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, 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 device 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 signal can be in the form of a DC mV output, 4-20 mA or from a platinum resistance thermometer. Please discuss prior to order.

Technical Feature Value
Reference Temperature Effectively 0°C
Temperature Gradient ±0.1°C between Junctions
Stability ±0.05°C per 1000 Hours
Ambient Range -20°C to +70°C
Accuracy ±0.1°C per 15°C ambient span
Stabilisation Time 10 mins
Thermocouple Capacity 0 to 100 channels double junction referencing
Power 10 Watts typical 100-130 or 208-240 VAC 50/60Hz Low level D.C. Consumption 6VA typical Passive Option Available.
Dimensions - Up to 50 Channels Height 255mm Width 483mm Depth 312mm
Weight 17.2kg
50 to 100 channels Height 309mm Width 483mm Depth 312mm
Weight 20.4kg
Numerous special versions are available and can be supplied either in their existing forms or modified to customers' requirements.
How to order Model 844 - Isoracs are normally uniquely specified for each order. Please discuss your exact requirements with us before ordering.