Computing the Total Load on a Fuse

You can calculate the total load on a fuse according to the circuit components and topology. You are therefore able to select the right fuse size at an early stage of the design. The current and the voltage drop are also computed.

Before you begin:
  1. From the Edition section of the action bar, click Electrical Calculation .
  2. Click a pin or a wire.
    A new window displays the fuse, the charges, and all electrical components between them. Information about the gauge is also displayed. For more information about electrical symbols, see About Symbols for Fuse Dimensioning.

    The current and the voltage drop are automatically computed. The fuse current can appear in three different colors depending on the value obtained after the current computation:

    • Red if the current computed in the fuse is higher than its nominal current.
    • Orange if the current computed in the fuse is higher than 0.8 x its nominal current.
    • Green if the computed current is lower than 0.8 x its nominal current.

  3. To lower the fuse current, click a charge to deactivate it.
    The charge and its harness connector are grayed out. The current is set to zero for the selected charge and the current of the other components is recomputed. The voltage drop is also recomputed. The current value for the fuse can change color.

    The voltage drop is computed on each wire, applying the following formula: ΔU[V] = resistivity[Ω.m] x Length[m] x Current[A] / section[m²].

    The voltage drop is computed starting from the fuse, then for each wire the formula is applied and the result is added to the ΔU of the previous wire.

  4. To edit the properties of a wire, double-click the name of the wire.
    The Properties panel appears. If you edit the values of the gauge or the cross section in the Reference tab, the current and the voltage drop are recomputed.