Identify temperature sensor

Question

Am wondering if anybody knows what type of sensor this is (from a build plate).

Perhaps a thermocoupler? The colouring of the wires seems to suggest it is not directional?

Would like to know details so that I can make use of it in my own projects.

Answer 1

It is quite likely not a thermocouple, but a thermistor:

• A thermocouple would look like a small blob of metal. The tip of your temperature sensor appears to be a glass bead, which is a commonly used way to encase thermistors.

• Thermocouples are polarized. The fact that the wiring is not "directional" suggests it is a thermistor.

• Thermocouples are used in high-temperature applications (such as a high-temperature hotend for printing specialty materials), where a thermistor would break down. The bed is not such a high-temperature application.

You can easily verify this with a multimeter. If it was a thermocouple, its resistance would be near zero. With a thermistor, you should see a decent amount of resistance (most 3D printing thermistors are 100k at room temperature).