skeshesh
Senior Member
- Location
- Los Angeles, Ca
Hope all is well with everyone.
I was looking over considerations for EGC sizing and I can't establish a gut feeling for when it's appropriate to actually worry about upsizing the wire size. I understand that the let-through current may exceed the ground wire insulation rating depending on the OCPD, but can't imagine this possibility warrants short circuit calculations for every point in a system. Is this mainly a problem in very large power systems where the bigger KVA rating allows for significant available fault currents? Would much appreciate anyone who's had experience with either a failure of a wire due to this condition or who's had to consider this conditions to shine some light on what constitutes a case where these calculations should be conducted as a good engineering practice.
I was looking over considerations for EGC sizing and I can't establish a gut feeling for when it's appropriate to actually worry about upsizing the wire size. I understand that the let-through current may exceed the ground wire insulation rating depending on the OCPD, but can't imagine this possibility warrants short circuit calculations for every point in a system. Is this mainly a problem in very large power systems where the bigger KVA rating allows for significant available fault currents? Would much appreciate anyone who's had experience with either a failure of a wire due to this condition or who's had to consider this conditions to shine some light on what constitutes a case where these calculations should be conducted as a good engineering practice.