This simple but most widely used sensor is designed and manufactured in two different configurations for long term and short term thermal observation. If used in a proper array it can precisely obtain the thermal gradient in any type of structure.

When used in short term observation, it can help to measure the concrete casting sequence in large casting steps, and when used as a long term monitoring device, it will obtain very useful information to monitor the health of structure over time.

Tamb = 25 °C; in liquid; unless otherwise specified.

Symbol Parameter Conditions Min Typ Max Unit
R25 sensor resistance Isen(cont) = 1 mA
1960 2040
TC temperature coefficient 0.79 %/K
R100/R25 resistance ratio Tamb = 100 °C and 25 °C 1.676 1.696 1.716
R-55/R25 resistance ratio Tamb = -55 °C and 25 °C 0.480 0.490 0.500
∆R25 drift of sensor resistance at 25 °C 10000 h continuous operation; Tamb = 150 °C 3.2
τth thermal time constant in still air [1] 30 s
in still liquid 5 s
in flowing liquid 3 s
Tamb ambient temperature -55 +150 °C
Logger CompatiblewithRUD600,RUD400 ,Central Readout units

[1] The thermal time constant is the time taken for the sensor to reach 63.2 % of the total temperature difference. For example, if a sensor with a temperature of 25 °C is moved to an environment with an ambient temperature of 100 °C, the time for the sensor to reach a temperature of 72.4 °C is the thermal time constant.

PIEZOMETERBorehole Deformation Gage