When two circuits cross each other, each of them behaves as a heat source for the other one. The amount of generated heat, the vertical distance between the crossing circuits and the crossing angle are the main parameters that influence the crossing rating.
In the absence of crossing calculations, the general practice is to use the conservative result where the circuits are assumed to be parallel. When the circuits are parallel, the thermal interaction is maximum. It goes to a minimum when they cross each other at a right angle. The conservative approach unnecessarily de-rates both circuits.
By using the Circuits Crossing module, one can achieve ratings up to 20% higher than the conservative ampacities that are obtained based on the parallel installation scenario.
Modeling features include:
- Modeling of two circuits crossings each other in the same installation
- Circuits crossing directly buried underground, in buried ducts and in buried pipes underground
- Rating approach as per the IEC standard 60287-3-3©