Building electrical knowledge: how to detect the fuse resistor

The detection of the fuse resistor. In the circuit, when fusing resistors fuse open, according to the experience to judge: if discover black or burning fuse resistor surface, can be concluded that the load is overweight, through many times more than its current rating; If there is no trace on its surface, it indicates that the current flowing through is equal to or slightly greater than its rated fuse value. For the determination of a fuse resistor with no trace on the surface, it can be measured by using the multimeter R * 1 block to ensure the accuracy of the measurement, and the end of the fuse resistor shall be welded down from the circuit. If the measured resistance value is infinite, it is indicated that the circuit breaker has failed to open, and if the measured resistance value is far from the nominal value, the resistance variable value is not suitable for reuse. In the maintenance practice, it is found that a few circuit breakers are short-circuited in the circuit, which should also be noticed in the detection.