HV Exit Exam • Set 6 Question 22 of 30

The fusing factor of a protective fuse is defined as the ratio of:

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Direct Answer

Option A: Minimum fusing current to rated current

Fusing factor is the ratio of Minimum Fusing Current (current that will melt the fuse) to Rated Current. For HRC fuses, this factor is typically 1.1 to 1.25.

All Options

Minimum fusing current to rated current (Correct Answer)

Rated current to minimum fusing current

Peak prospective fault current to rated current

Breaking capacity to making capacity

Detailed Explanation & Context

Fusing factor is the ratio of Minimum Fusing Current (current that will melt the fuse) to Rated Current. For HRC fuses, this factor is typically 1.1 to 1.25.

Relevant Framework: STCW 2010 Manila Amendments • DG Shipping E-Learning & Exit Exam Standards • High Voltage Safety Officer & Switchgear Operations (HV).

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