Resistance thermometer for indoor or outdoor ambient
Reliable measurement and high accuracy - Best protection of the measuring
electronics from extreme ambient conditions. Applicable for wall mounting.
- Indoor or outdoor ambient temperature measurement
- Maximum measuring range: –50 to +100 °C (–58 to +212 °F)
- Degree of protection: IP66/68 (NEMA Type 4x encl.)
All Endress+Hauser transmitters are available with enhanced
accuracy and reliability compared to directly wired sensors.
Easy customizing by choosing one of the following outputs and
- Analog output 4 to 20 mA
- HART ®
- PROFIBUS ® PA
- FOUNDATION FieldbusTM
- Robust terminal heads according to DIN EN 50446 or stable plastic housings offer optimal protection from extreme ambient conditions
- Reliable, long term stable and accurate indoor or outdoor ambient temperature measurement
- Simple and fast wall mounting
These resistance thermometers use a Pt100 temperature sensor according to IEC 60751. The
temperature sensor is a temperature-sensitive platinum resistor with a resistance of 100 Ω at
0 °C (32 °F) and a temperature coefficient α = 0.003851 °C -1 .
There are generally two different kinds of platinum resistance thermometers:
Wire wound (WW): Here, a double coil of fine, high-purity platinum wire is located in a ceramic
support. This is then sealed top and bottom with a ceramic protective layer. Such resistance
thermometers not only facilitate very reproducible measurements but also offer good long-term
stability of the resistance/temperature characteristic within temperature ranges up to
600 °C (1 112 °F). This type of sensor is relatively large in size and it is comparatively sensitive to
Thin film platinum resistance thermometers (TF): A very thin, ultrapure platinum layer,
approx. 1 μm thick, is vaporized in a vacuum on a ceramic substrate and then structured
photolithographically. The platinum conductor paths formed in this way create the measuring
resistance. Additional covering and passivation layers are applied and reliably protect the thin
platinum layer from contamination and oxidation, even at high temperatures.
The primary advantages of thin film temperature sensors over wire wound versions are their smaller
sizes and better vibration resistance. A relatively low principle-based deviation of the resistance/
temperature characteristic from the standard characteristic of IEC 60751 can frequently be observed
among TF sensors at high temperatures. As a result, the tight limit values of tolerance category A as
per IEC 60751 can only be observed with TF sensors at temperatures up to approx. 300 °C (572 °F).
For this reason, thin-film sensors are generally only used for temperature measurements in ranges
below 400 °C (752 °F).