Two details of the temperature sensor are easily overlooked

The principle and installation of the temperature sensor have been said a lot, and most people already understand it, but there are two details in the use of the temperature sensor are easily overlooked. One is its operating temperature, and the other is its insertion depth.

   The normal operation of the temperature sensor element is to meet its working conditions, one of which is its operating current. Since the temperature sensor has a resistance value, when the current flows through the temperature sensor element, there will be power loss, which will generate heat, so Decreasing the heat generated by the sensor itself causes the temperature measurement error, so it is necessary to reduce its own heat as much as possible under the condition that the sensor is working normally. This is why the temperature sensor is used under constant low current conditions. So the normal operating current of a platinum RTD is 5MA, but our recommended operating current is 1MA. The reason is to reduce the measurement error caused by the self-heating of the temperature sensor element. The current is constant and its output has a linear relationship between temperature and potential.

    The insertion depth of the temperature sensor is also a problem that is easily overlooked. Some customers require a short insertion depth but a large diameter, which is unreasonable, especially in the case of high temperatures. Theoretically, the temperature sensor is inserted. The depth can generally be determined according to actual needs. However, the minimum insertion depth should not be less than 8-10 times the diameter of the temperature sensor protection sleeve. This will ensure the stability of the temperature sensor performance.

    Understanding the operating current and insertion depth of the temperature sensor is necessary for us to select and use the temperature sensor. If you ignore these two details, it is easy to cause the temperature sensor performance to be unstable or even damaged.