Is it permissible to have 34.5kV feeder in overhead rigid conduit for a short distance in an outdoor installation? Situation is as follows:
A new 34.5kV feeder is being installed to feed the primary of the transformer. The feeder will be run underground the majority of the run but because the transformer is existing and surrounded by an oil containment pit it will be difficult (if not impossible) to continue new feeder underground needing to penetrate through existing oil containment pit and existing transformer slab.
My thought was to stub up the UG feeder just outside the oil containment pit (aprox 10-15 feet away from transformer primary) and then transition to overhead to get over to transformer primary termination cabinet. I'm looking for feedback on best approach to this based on others experience. Some options I've thought of are:
1) Stub up UG feed and transition to rigid conduit run on the ground across the top of oil containment pit and slab to transformer primary. This could present a trip hazard and I'm not sure is code complaint.
2) Stub up UG feed and transition rigid conduit up a support structure to elevate it to 8-10 feet to then cross over to transformer primary enclosure.
3) Stub up UG feed and transition to cable tray up a support structure to elevate 8-10 feet then cross over to transformer primary enclosure. Cable tray may present additional challenges with trying to enter into transformer primary ATC.
4) Create some sort of custom pull box which extends the transformer primary ATC and sits over the existing slab and containment pit to be able to pick up UG conduit.
A new 34.5kV feeder is being installed to feed the primary of the transformer. The feeder will be run underground the majority of the run but because the transformer is existing and surrounded by an oil containment pit it will be difficult (if not impossible) to continue new feeder underground needing to penetrate through existing oil containment pit and existing transformer slab.
My thought was to stub up the UG feeder just outside the oil containment pit (aprox 10-15 feet away from transformer primary) and then transition to overhead to get over to transformer primary termination cabinet. I'm looking for feedback on best approach to this based on others experience. Some options I've thought of are:
1) Stub up UG feed and transition to rigid conduit run on the ground across the top of oil containment pit and slab to transformer primary. This could present a trip hazard and I'm not sure is code complaint.
2) Stub up UG feed and transition rigid conduit up a support structure to elevate it to 8-10 feet to then cross over to transformer primary enclosure.
3) Stub up UG feed and transition to cable tray up a support structure to elevate 8-10 feet then cross over to transformer primary enclosure. Cable tray may present additional challenges with trying to enter into transformer primary ATC.
4) Create some sort of custom pull box which extends the transformer primary ATC and sits over the existing slab and containment pit to be able to pick up UG conduit.
