Refers to cable sizing tool 10th line. Is it : No of cables/circuit ?

Can you please explain the difference

asked 5/17/2012

2 Answers

In addition to caj’s answer, I’ve also just added a post to the notes section going into more detail on how the sizing tool works.

If you still have questions, please ask.
answered 5/20/2012 Steven McFadyen 246
Steven McFadyen
A circuit is generally everything protected by one device. There can be more than one cable in a circuit. The cables may run in parralel when the circuit needs to carry more current than avalible cables can carry.

You have multiple circuits (that may conist of 1 or more cables) when the cables of more than one circute are close together and the heating affect of one cable affects another. This is found where cables are grouped together when the leave switch gear. As well as when multiple circits are run on the same cable tray or in the same trunking.
answered 5/18/2012 caj 1

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