Technical Support on Circuit Breaker Selectivity in Ecodial

[Ahmad3]

We are currently facing difficulties in achieving full selectivity between the circuit breakers in our Ecodial studies. In several cases, the software indicates “Selectivity Limit” or “No Selectivity.”

In this regard:

1. What are the recommended measures or settings that can be applied in order to achieve full selectivity between the upstream and downstream breakers?

2. Do the cable sizes and lengths play a significant role in the selectivity coordination, and to what extent should these parameters be considered when attempting to improve selectivity results?

[Kleeh · Accepted solution]

1. The selectivity tables provided by Schneider Electric gives some tipss on the expected selectivity results. It's useful to look at it in order to choose the right circuit breakers upstream or downstream according to the selectivity result that you want.

2. Yes, sometimes the selectivity results depends on the short-circuits level which are linked to cable sizes and lengths in some extent.