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9.7 kVA Step-Down Buck-Boost Transformer, 240V → 256V, 21.9A, Three Phase
$746.75
9.7 kVA three-phase buck-boost that bucks 240V to 256V (7% correction) at 21.9A. Encapsulated NEMA 3R, cETLus listed. In-stock ships same business day.
Ships in 2-3 weeks
Inventory & Inbound
0 currently in stock
- 30 more available, earliest Jul 21, 2026
Projected inbound quantities and dates are based on current purchase orders with our suppliers and are not guaranteed. We update them as suppliers confirm.
Specifications
| Brand | Sanzo Sales |
| Phase | Three Phase (3-PH), Delta |
| Capacity | 9.7 kVA |
| Primary Voltage | 240V |
| Primary Amperage | 23.3A |
| Secondary Voltage | 256V |
| Secondary Amperage | 21.9A |
| Maximum Primary OCP | 30A |
| Frequency | 50/60 Hz |
| Insulation | 180°C |
| Temperature Rise | 115°C |
| Part # | TX-BB-240D-256D-22A |
| Transformer Type | Buck/Boost |
| 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 |
Product Description
The TX-BB-240D-256D-22A is a 9.7 kVA three-phase buck-boost transformer that bucks a 240V supply to 256V — a 7% voltage correction — bringing 256V-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 21.9A at 256V (9.7 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. Supplied as a two-unit open-delta bank for three-phase delta service. In-stock units ship the same business day.