Campus BTM GSU - 400 MVA · 345/18 kV

Where this class sits on a one-line

A 400 MVA, 345/18 kV shape serves a large behind-the-meter generation block that must step up to a 345 kV collector or interconnect. The 18 kV class LV matches large gas-turbine and combined-cycle generator terminals, which OEM education usually places between the mid-teens and about 25 kV. The 345 kV HV side ties into the transmission-class yard that most large North American campuses interconnect through.

This unit appears when a campus adds on-site generation. It does not replace the utility step-down transformer. A campus that only takes utility power buys an interconnect LPT instead, so confirm the role on the one-line before the RFQ goes out.

Spec decisions to settle before the RFQ

State the MVA per cooling stage, since a nameplate without ONAN, ONAF, or ODAF context is incomplete. Give the %Z as a band if two OEM channels will be compared, and as an exact value only when the unit must parallel or replace an existing tank. BIL follows the 345 kV yard coordination study.

Many GSU applications regulate voltage through the generator excitation system and use a de-energized tap changer. Specify an OLTC only when the study requires one, because it adds cost, a long-lead component, and a maintenance item. Vector group must match generator grounding and the HV protection study, or be marked TBD for the OEM to propose.

FAT, transport, and evidence

Put factory acceptance test witness rights, the test list, and the governing standard in the purchase contract. IEEE C57.12.90 (2021) is the usual North America test code reference. A tank in this class typically moves under state oversize and overweight permits, often by rail or Schnabel car for the long leg, so the haul plan and impact-recorder handling belong in the same evidence pack as the FAT certificate.

Lead time and capital context

Industry surveys keep GSU clocks long. Wood Mackenzie survey data reported through ACP in Q2 2025 put average GSU lead times near 143 weeks. That figure is a labelled market survey, and it is separate from the catalog ARO band on this listing, which is a target confirmed on quotation. Supplier deposits on a unit like this can be flagged for working-capital review on the quote form. A licensed partner underwrites when eligible.