In actual use, the fuse should pay attention to the following aspects:
First, the protection characteristics of the fuse should be integrated into the load characteristics of the protection target. Fully consider the possible short-circuit capacity, and select a circuit breaker with corresponding splitting ability;
Second, the rated current of the fuse should be integrated into the rated voltage of the route, and the rated voltage of the fuse should be greater than or equal to the rated voltage of the circuit breaker;
Third, the solution rated voltage of each fuse in the route should cooperate with each other, and the rated voltage of the previous level of solution must exceed the rated voltage of the next level of solution;
Fourth, the fuse solution should cooperate with each other as required, and the solution cannot be lifted at will or replaced by other electrical conductors.
Choose a circuit breaker based on the following factors:
1. Select the type and specification of the fuse according to the route regulations and installation standards. The small-volume power supply circuit is semi-enclosed or enclosed without packing; the short-circuit capacity is enclosed with packing; the fast fuse is used for the maintenance of semiconductor material components.
2. Select the rated current of the fuse according to the line operating voltage.
3. Select the rated voltage of the fuse according to the load characteristics.
4. The choice of each solution must cooperate with each other, and the latter level is smaller than the former level. The current of the main hydraulic gate and each branch line is different, and the choice of fuse is also different. If the line is shorted, the 15A and 25A solutions will be blown at the same time, and the maintenance feature will lose selectivity. So this will not happen only if the main hydraulic gate and the branch maintain a 2-3 level difference. For example, the inlet and outlet of the low-voltage side of the transformer are RT0100/800. The motor is RT0400/250 or RT000/350, and the ratio of rated voltage of each department is 3.2 and 2.3, so the selectivity is better, that is, the short-circuit fault of the branch line, and the commercial insurance integration of the branch line will not affect the power supply system of the main water conservancy gate.
5. The solution should not be too small. If the selection is too small, it is easy to blow the one-phase fuse, causing the single-phase electric operation of the motor to burn out; according to the survey, 60% of combustion motors are caused by unreasonable fuse configuration.
Post time: Jun-21-2022