First, the working principle

The temperature of the equipment rises abnormally, and the temperature fuse (thermal fuse) feels the ambient temperature. When the temperature reaches the melting point of the fusible alloy, the fusible alloy melts. Under the action of the special resin, the melted alloy rapidly shrinks into a ball, thus cutting off the current.

Two, operation temperature test method

1. EQUIPMENT:

1) A THERMOMETER

2) SILICON OIL BATH

3) STIRRER

4) SAMPLE

5) FIXTURE fixture

6) Light emitting diode LED

7) current-limiting RESISTOR

8) The HEATER

2 Test method:

Connect the two pins of the sample respectively to the fixture of the test equipment, connect the detection current of about 10 MA (the maximum is not more than 100 MA), and use a light-emitting diode to indicate the on-off of the detection current. The temperature of the silicone oil pool should be stabilized at TF-10℃ (the silicone oil pool should be equipped with an agitator to ensure uniform temperature, and the heating rate can be controlled), and then the sample should be put into the silicone oil pool. The thermometer probe should be as close as possible to the sample, and the temperature of the silicone oil pool should be controlled to rise at the rate of 0.5-1℃ per minute. When the LED is turned off, the thermometer reading should be recorded, including the operating temperature of the sample.

(If there is no oil pool test equipment, you can also test in a thermostat with a blast device, but you must pay attention to the thermometer probe close to the sample to obtain accurate results)