Short Circuit Calculations and Conduit Material

I recently came across a previous study that was completed for a facility that assumed a specific type of conduit [non-metallic/magnetic; PVC] vs what was actually installed [Rigid Meal Conduit], in digging into this deeper and looking at some of the short circuit calculations information available to me it appears that in the calculation they type of conduit [magnetic vs non-magnetic] can play a role in the amount of available fault current. When doing some quick simplistic calculations it appears that the conduit material does play a role and in larger systems could make a difference. I did some digging in my software’s reference material and some other material but could not find adequate explanation / technical data.

I was hoping someone could share or point me to some additional resources on how conduit material affects available fault current? It appears there are different constants for conductors based on the type of installation [conduit type for systems of .208-13.2kV] also what if you have conductors installed in tray [3-1/C cables] does the spacing and configuration of how the cables are installed come into play and where could I find some information on this. Thanks in advance. READ MORE.


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