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28.77 kVA Step-Down Buck-Boost Transformer, 115V → 105V, 274A, Single Phase
$1,210.05
28.77 kVA single-phase buck-boost that bucks 115V to 105V (9% correction) at 274A. Encapsulated NEMA 3R, cETLus listed. In-stock ships same business day.
✔ In Stock: 4
Specifications
| Brand | Sanzo Sales |
| Phase | Single Phase (1-PH), AC |
| Capacity | 28.77 kVA |
| Primary Voltage | 115V |
| Primary Amperage | 250A |
| Secondary Voltage | 105V |
| Secondary Amperage | 274A |
| Maximum Primary OCP | 350A |
| Frequency | 50/60 Hz |
| Insulation | 180°C |
| Temperature Rise | 115°C |
| Transformer Type | Buck/Boost |
| Part # | TX-BB-115V-105V-274A |
| Configuration | Encapsulated Autotransformer |
| Primary Termination | Lead Wires & Terminal Lugs |
| Secondary Termination | Lead Wires & Terminal Lugs |
| Termination Access | (6) ¾" NPT Hubs |
| Winding Material | Aluminum |
| Enclosure Material | Steel |
| Finish Color | ANSI 70 Light Grey |
| Weatherproof Rating | NEMA 3R |
| Certification Listing | cETLus |
| Dimensions (W×H×D) | 7.68 × 12.2 × 6.38 in |
| Weight | 60 lb |
Product Description
The TX-BB-115V-105V-274A is a 28.77 kVA single-phase buck-boost transformer that bucks a 115V supply to 105V — a 9% voltage correction — bringing 105V-rated equipment back into its proper operating range. Wired as an encapsulated buck transformer (autotransformer), it carries only the correction portion of the load, so this unit corrects a much larger connected load: up to 274A at 105V (28.77 kVA usable line capacity).
Resin-encapsulated in a NEMA 3R steel enclosure (ANSI 70 light grey) for indoor or outdoor mounting at the disconnect. Lead wires and terminal lugs, aluminum windings, 180°C insulation system, 115°C rise, 50/60 Hz, cETLus listed. Use two units in open-delta for three-phase delta systems, three for wye. In-stock units ship the same business day.