A fuse is an overcurrent protection device that interrupts the circuit when the current exceeds a given value for a given period of time. The fuse will not trip while the current remains below the nominal current I_N.

A tripped fuse can be reset during the simulation by clicking it with the mouse. However, it will trip again if the current was not reduced.

In FluidSIM, fuses are modeled by a general fuse, the tripping characteristics of which can be specified as a trip curve. The trip curve is a curve describing the relationship between the current intensity and the trip time. The curve is defined by two points. The two points can be defined by the user by selecting User Defined.

The first point is the time when the fuse trips if ten times the nominal current is applied constantly. The factor c1h is specified in FluidSIM for the second point. At a constant current intensity of c1h * I_N the fuse trips after exactly one hour. This factor can be found in the manufacturer's specifications.

If the user selects FF (Very Fast Acting), F (Fast Acting), M (Medium Acting), T (Slow Acting) or TT (Very Slow Acting), an average value will be selected automatically for the first time point.

Adjustable parameters

Designation Range Default value
Tripping characteristic User Defined, FF (Very Fast Acting), F (Fast Acting), M (Medium Acting), T (Slow Acting), TT (Very Slow Acting) M (Medium Acting)
Rated current 0.01 ... 10000 A 5
Tripping time (10*I_N) 0.0001 ... 10 s 0.02
Factor Rated current (Tripping time 1h) 1.21 ... 9.9 1.5
Resistance 0.0001 ... 100 Ohm 0.01

Failure models

Failure model Description
Fuse blown The tripped fuse interrupts the current flow.