The fuse breaking current of the patch fuse is 1.5 to 2.0 times the rated current. When electrical equipment is in normal use, its fuse will not break. When the current in the circuit exceeds 5 times its rated current, it will automatically break to provide protection. If the fuse melts during normal use of electrical equipment, it indicates that the current in the circuit exceeds the rated current. Therefore, the cause should be immediately investigated.
During the installation process of patch fuses, it is necessary to first pull off the switch on the distribution board and cut off the power supply. It is better to use an electric pen to test whether there is power before operating. For fixing screws and washers, copper should be used instead of iron temporarily, as iron can easily rust and lead to poor contact over time. When tightening the fuse, do not use excessive force to prevent the fuse from being flattened and causing a reduction in the cross-sectional area, rated current, and melting current, which may not have the desired "safety" effect.
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