When the high-voltage current-limiting fuse is selectively matched with the low-breaking capacity electrical appliance, in this case, the current-limiting fuse acts under the large fault current, and the low-breaking capacity electrical appliance can only break the small current it allows, so it needs to be realized according to the different time-current curves of the two.
1. Taking the intersection point of the curve as the boundary, the current-limiting fuse bears the breaking of large fault current, and other electrical appliances bear the breaking of normal current and small fault current.
2. If other electrical appliances are not interlocked and tripped with the fuse impactor, the intersection point must be greater than the minimum action current of the high-voltage current-limiting fuse.
3. The current at the curve intersection point must be less than the breaking capacity of other electrical appliances.
4. When the high-voltage current-limiting fuse is used to break the circuit, other electrical appliances must have sufficient capacity to pass the short-circuit current and make the short-circuit current (the thermal stability and dynamic stability of the appliance should be verified by its breaking current and making current). These capacities should be consistent with the cut-off current and I of the high-voltage current-limiting fuse ² T value.
5. If other electrical appliances are interlocked and tripped with the fuse impactor, such as the load switch, the allowable transfer current value of the load switch is required to be greater than the maximum transfer current value of the fuse.
