When we get a Fuser thermistor, but don't know whether it is good or bad, we can use a child labor multimeter to check whether it is good or bad. Then, how do we use a multimeter to check whether the Fuser thermistor is good or bad? What should I pay attention to when testing Fuser thermistor? Let's take a look.

When testing, use the multimeter's ohm level (depending on the nominal resistance value to determine the level, generally R×1 level), and the specific operation can be divided into two steps: first, room temperature detection (the indoor temperature is close to 25°C), and the alligator clip is used instead of the test pen to clip separately The actual resistance of the two pins of the PTCFuser thermistor is measured and compared with the nominal resistance. The difference between the two is within ±2Ω, which is normal. If the actual resistance value differs too much from the nominal resistance value, it means that its performance is poor or damaged.
Secondly, heating test. On the basis of normal temperature test, the second step of test—heating test can be carried out. Place a heat source (such as an electric soldering iron) close to the Fuser thermistor to heat it, and observe the universal indicator. The universal indication changes with the increase of temperature, which indicates that the resistance value is gradually changing (the resistance value of NTC of the negative temperature coefficient Fuser thermistor will become smaller, and the resistance value of the PTC of the positive temperature coefficient Fuser thermistor will become larger). When the value changes to a certain value, the displayed data will gradually stabilize, indicating that the Fuser thermistor is normal. If the resistance value does not change, it indicates that its performance has deteriorated and cannot be used continuously.
The precautions for detecting Fuser thermistor are as follows:
1) Rt is measured by the manufacturer when the ambient temperature is 25°C, so when measuring Rt with a multimeter, it should be run at an ambient temperature close to 25°C to ensure the reliability of the test.
2) The measured power shall not exceed the specified value, so as to avoid the measurement error caused by the heating effect of the current.
3) Pay attention to correct operation. During the test, do not pinch the Fuser thermistor with your hands to prevent the body temperature from affecting the test.
4) Be careful not to make the heat source too close to the PTCFuser thermistor or the clock touches the Fuser thermistor to prevent it from being burned.
The detection methods and precautions shared above are hoped to be helpful to everyone.