Transmission conductor midspan phase - phase clearance
Transmission conductor midspan phase - phase clearance
(OP)
The NESC does not specifically address ph - ph clearance so I have a two part question:
what criteria are people using to determine ph - ph midspan clearance?
What will happen if the phases get too close? Is there a potential for issues with induction?
Thanks,
-Ethan
what criteria are people using to determine ph - ph midspan clearance?
What will happen if the phases get too close? Is there a potential for issues with induction?
Thanks,
-Ethan






RE: Transmission conductor midspan phase - phase clearance
One other factor to consider is construction consistency. In vertical construction, just a small difference in tension between two phases can result in a pretty significant difference in sag.
What do you mean by induction? Changing the phase to phase clearances would change the impedance of the line, but that is different from a three phase power line causing induction in some other nearby cable.
In some instances, we scale up the clearance listed for distribution voltages for our transmission system. In others, it is based on standard lattice tower designs. In long span crossing applications, each one is evaluated separately.
Utility is areas with raptor problems sometimes have phase to phase spacing large enough to prevent the birds from touching two phases at once.
Mark
RE: Transmission conductor midspan phase - phase clearance
Another consideration is conductor galloping if you are in an area that has icing.
RE: Transmission conductor midspan phase - phase clearance
GO-95 The california Overheal line rules ht
RE: Transmission conductor midspan phase - phase clearance