What are temperature sensors and what are they used for?
Temperature sensors measure the temperature of air, objects, materials, or liquids. They are used in a wide variety of applications, such as monitoring processes, environmental conditions, or electronic devices.
In order to choose the right temperature sensor, you should carefully consider what measuring range and accuracies you need.
What types of temperature sensors are available?
We offer resistance sensors, sensors with linear output and digital sensors.
Resistance sensors
- Pt100 class B
- Pt100 class A
- Pt100 class 1/3 class B
- Pt100 class 1/10 class B
- Pt500 Class B
- Pt1000 Class B
- Pt1000 Class A
- Ni1000
- KTY 81-210
- KTY 81-110
Sensors with linear output
Digital sensors
How do PTC and NTC temperature sensors work?
PTC (Positive Temperature Coefficient) and NTC (Negative Temperature Coefficient) sensors respond differently to temperature changes.
PTC sensors have a positive thermal coefficient. They increase their resistance value at higher temperature. NTC sensors, on the other hand, have a negative thermal coefficient. They, in turn, decrease their resistance when the temperature is increased.
What is the difference between a Pt100, a Pt500 and a Pt1000 sensor?
The number after the Pt indicates the resistance value at temperature 0 °C. For example, the Pt100 has a resistance value of 100 Ω at 0 °C and the Pt1000 of 1000 Ω.
Which Pt sensor is the most suitable usually depends on the input of the control unit. In addition, it makes sense to use a Pt1000 for a longer cable, since the base resistance of a Pt1000 is ten times higher than that of a Pt100.
What does the IEC 60751 standard say about accuracy?
According to the IEC 60751 standard, there are different accuracies for Pt sensors.
- Class B dT = ±(0.30 °C + 0.005|t|)
- Class A dT = ±(0.15 °C + 0.002|t|)
- 1/3 Class B dT = ±(1/3 - (0.30 °C + 0.005|t|))
- 1/10 Class B dT = ±(1/10 - (0.30 °C + 0.005|t|))
We offer all accuracy classes for Pt100 sensors, class B for Pt500 sensors and class B and A for Pt1000 sensors.
How can you detect a defective temperature sensor?
To detect a defective Pt sensor, it is best to take a digital multimeter, or similar measuring device. Set the resistance measurement.
Then you can connect the measuring device to the contact points of the Pt sensor.
When you measure the resistance of the Pt sensor, take a resistance table or an online calculator and calculate the temperature that matches it.
Compare this temperature with the actual ambient temperature.
If the resistance value is 0 Ω, however, the sensor has a short circuit. If the resistance value is many times higher than the expected resistance value, the sensor has a break.
