Buck-boost transformers are small, single phase, dry type distribution transformers designed and shipped as insulating/isolating transformers. They have a dual voltage primary and a dual voltage secondary. These transformers can be connected for a wide range of voltage combinations. The most common use is to buck (lower) or boost (raise) the supply voltage a small amount, usually 5 to 27%. Buck-boost transformers comply with NEC article 210-9, exception 1, when field connected as an auto transformer.

GE Industrial Solution Buck Boost Transformer, Type QB Dry Encapsulated Enclosed Small Power Standard, Series: 9T, 240 VAC Primary, 120 VAC Secondary, 1.5 kVA, 60 Hz, 1 ph, Screw Terminal, Wall Mount, IS-12, NEMA 3R, 40 deg C, Silicon Steel Housing, 7.88 in W x 9.62 in H

• https://externalassets.unilogcorp.com/ASSETS/DOCUMENTS/ITEMS/EN/GE_9T51B0139_Specification_Sheet.pdf https://www.iesbuy.com//ASSETS/DOCUMENTS/ITEMS/EN/https://externalassets.unilogcorp.com/ASSETS/DOCUMENTS/ITEMS/EN/GE_9T51B0139_Specification_Sheet.pdf

• These GE transformers feature encapsulated core and coils in a NEMA 3R non-ventilated weatherproof enclosure
• Knockouts provided on back and bottom
• High grade silicon steel core
• Mounting holes on side for easy access
• Wiring compartment includes ground stud
• Efficient insulating materials permit compact size and lightweight
• Dual voltage primary and dual voltage secondary for maximum versatility
• Large, front accessible wiring compartment permits fast, easy wiring
• Convenient conduit knockouts located on side, bottom and back of wiring compartment
• Convenient method of matching line voltage with equipment voltage
• Ability to handle loads up to 20 times nameplate rating when connected as an autotransformer
• Ideal for changing line voltages by small amounts