For non-time-delay fuse sizing, what percentage of FLA is used?

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Multiple Choice

For non-time-delay fuse sizing, what percentage of FLA is used?

Explanation:
For non-time-delay fuses, you size the fuse around 300% of the motor’s full-load current (FLA). The reason is that motors draw a large surge current when starting up, much higher than the running FLA. A fast-acting (non-time-delay) fuse must be large enough to tolerate that startup inrush without nuisance blowing, yet still provide protection against a short circuit. Using about three times the FLA strikes that balance: it allows the motor to start reliably while still protecting the circuit from sustained overcurrent faults.

For non-time-delay fuses, you size the fuse around 300% of the motor’s full-load current (FLA). The reason is that motors draw a large surge current when starting up, much higher than the running FLA. A fast-acting (non-time-delay) fuse must be large enough to tolerate that startup inrush without nuisance blowing, yet still provide protection against a short circuit. Using about three times the FLA strikes that balance: it allows the motor to start reliably while still protecting the circuit from sustained overcurrent faults.

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