Interconnect LPT - 300 MVA · 345/34.5 kV

The default campus energization unit

A 300 MVA, 345/34.5 kV LPT steps a transmission corridor down to the medium-voltage bus that feeds campus distribution. For a utility-served North American data-center campus this is the default long-lead unit, and it usually gates energization: the buildings can finish long before the yard can take power.

Campuses in this class commonly buy two or more matched units for an N+1 or dual-feed yard. That choice turns impedance from a data-sheet line into a procurement constraint.

%Z interchange for dual-unit yards

Two tanks that share load must sit inside a matched impedance band, or one unit takes more than its share of current and the pair derates. When the two tanks may come from different OEMs, the RFQ has to state the %Z band both must hit, plus the tolerance the study can absorb. Asking for exact impedance from a single OEM is easy. Getting two factories into the same band takes an explicit spec line and a review of test reports at FAT.

Bushings and co-gate risk

HV bushings are bought-out components with their own clocks, and OEM component boards in 2026 discussed high-voltage bushing classes on the order of 145 weeks. A tank can be wound and assembled while its bushings still gate the ship date. Ask each bidder how bushing supply is secured for the quoted schedule, and put the answer in the bid record.

Standards, lead time, and deposits

IEEE C57 is the usual North America standards path, with IEC 60076 as the dual-path or import option. The catalog ARO on this listing is a target confirmed on quotation, while 2024 Wood Mackenzie commentary placed many large substation and GSU units in an approximately 80 to 210 week band. Supplier deposits and progress payments on this class can be flagged for working-capital review by a licensed partner on the quote form.