Dr Paul Hayden
Instrument Support Level 3
Thermistors are passive components that change their resistance with temperature. We have more than one hundred of these, measuring temperature around the lab with a resolution of better than 0.005 deg C and an accuracy of around 0.05 deg C. It’s response time is a few seconds.
The diameter of the blue head is just over 1mm. The black box made in-house contains an Arduino which we talk to via RS485 with EnFlo Software.
These temperatures are measured with a frequency of about 0.5Hz.
Thermistors change their resistance with temperature. Electronics have been built to accurately measure this resistance change, and produce a linearized temperature output.
The first thermistor we built was calibrated against a lab glass bulb thermometer and called the Master reference thermistor. Every subsequent thermistor we offset against the master reference, since we are not really interested in the absolute temperature, but want all our thermistors in the lab to read within 0.05 deg C of each other. Temperature differences are most important to us since these drive the buoyancy forces.
From time to time we check the thermistors against the master reference.
- The instrument produces a range of out files and all are text format.
- The user can download (but not delete) this data from the instrument but it should be noted that this data will not have been quality controlled.
- The Data file format will be the same as for the LDA Data. Only mean values of temperature are given since this is not a “Fast Response” instrument. The plot shows the temperature profiles for the inlet to the tunnel, and a rake downstream in neutral conditions. These profiles confirm that the temperature uniformity is within about 0.05 Deg C, indicating that we do have a very uniform temperature profile
- Instrument name is
- Under development
- The data product(s) associated with this instrument:
- Under development