IEC 61660-3 which is a technical report gives help for the application of IEC 61660-1 and IEC 61660-2. Therefore, the calculations for the d.c. installation in figure 1 are strictly carried out in accordance with IEC 61660-1 and 61660-2.
The installation scheme with respect to the short-circuit location F3 in figure 1 does not correspond to figure 3 of IEC 61660-1. Therefore, additional considerations related to the correction factor σj are necessary and annex A should be consulted.
The connecting line L1 in figure 1 consists of copper bars (see clause 4). The lines L2 and L3 are cable connections. Therefore, the mechanical and thermal effects are calculated only for L1 in case of a short circuit at the location F4.