What Type Of Fuse Should Be Used When The Rated Current Of The Distribution Transformer Is 100a?

When a transformer is put into operation, short-term current surges may occur during initial magnetization inrush current or load startup. If a 100A fuse is selected for the drop out fuse transformer, it is highly likely to trip due to the instantaneous current peak, affecting system stability. In such cases, a fuse with a rated current of 125%–150% of the transformer's rated current is typically chosen.

Both 125A and 150A fuses have specifications exceeding the transformer's rated load current. This design balances the transformer's normal operation with its inrush current characteristics. If a short-term large current occurs during load changes or startup, the fuse will not trip falsely, thus ensuring power supply continuity and stable equipment operation.