Fusing Current Calculator, Formula, Fusing Current Calculation

Fusing Current Calculator:

Enter the values of fusing factor, FF and current rating, CR_(A) to determine the value of Fusing current, I_f(A).

Fusing Current Formula:

Fusing current refers to the minimum current level required to cause a fuse to melt and disconnect the electrical circuit it is protecting.

The fusing factor is typically greater than 1, indicating that the actual fusing current is higher than the nominal current rating of the fuse.

This factor accounts for variables such as ambient temperature, the aging of the fuse material, and the potential for short but high current spikes that do not pose a sustained risk.

In practice, the fusing current determines the threshold at which a fuse will reliably operate to protect the circuit.

Fusing Factor, which is a multiplier that considers the characteristics of the fuse material, including its melting point and thermal properties.

Current Rating, which is the nominal current value the fuse is designed to carry safely under normal operating conditions.

Fusing current, I_f(A) in amperes is calculated by the product of fusing factor, FF and current rating, CR_(A) in amperes.

Fusing current, I_f(A) = FF * CR_(A)

I_f(A) = fusing current in amperes, A.

FF = fusing factor.

CR_(A) = current rating in amperes, A.

Fusing Current Calculation:

1. Given a fusing current of 15 amperes and a fusing factor of 1.2, calculate the current rating.

Given: I_f(A) = 15A, FF = 1.2.

Fusing current, I_f(A) = FF * CR_(A)

CR_(A) = I_f(A) / FF

CR_(A) = 15 / 1.2

CR_(A) = 12.5A.

2. Calculate the fusing current for a circuit protection device with a fusing factor of 1.25 and a current rating of 20 amperes.

Given: CR_(A) = 20A, FF = 1.25.

Fusing current, I_f(A) = FF * CR_(A)

I_f(A) = 20 * 1.25

I_f(A) = 25A.

Understanding Current Limit Fuses and let through current