Thin Film Thermometer MTFT
Application
Thin film thermometers consist on a ceramic substrate of zirconium oxide on which a thin film of nickel is deposited. This sensor is a magnitude more sensitive than our thermocouples. Temperature changes of only 0.1 K can be measured. The gauges can measure static to high transient surface temperatures with response times in the range of microseconds.
Due to the open metal film these sensors are quite sensitive but also delicate. Therefore for measurements in clean conditions and moderate heat fluxes the Thin Film Thermometer are recommended, whereas in harsh environmental conditions or high heat fluxes our Coaxial Thermocouples MCT is the better choice.
The MTFT are powered by a constant current source. The change of the film resistance leads to voltage changes proportional to the temperature change. The temperature change corresponds to
ΔT = (R – R0) / R · α
For transient temperature changes the Thin Film Thermometer may be connected to our MFA 1000 Amplifier and power supply. This device has a bridge amplifier and offers constant current and voltage. Alternatily any other bridge amplifier could be used.
Technical Data
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Thin film material: |
Nickel |
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Substrate: |
Zirconium Oxide |
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Smallest measurable temperature change: |
0.1 K |
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Responds time: |
< 10 μs |
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Resistance: |
25 to 50 Ohm |
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Sensitivity: |
α = 0.002 to 0.0025/K |
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√p c k |
About 0.35 J/(K cm² √s) |
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Power supply: |
Constant current 7 – 10 mAh |
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Diameter: |
2.3 mm ± 0.1 mm |
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Length: |
3.3 mm |
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Calibration: |
Delivered calibrated by University Aachen |
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Periphery: |
The thin film thermometer needs a constant current source and an amplifier. The type of periphery depends on the application. |
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In case of transient measurements with high bandwidth we recommend our MFA 1000, which provides the constant current source and a bridge amplifier in one device with 1 MHz bandwidth |