Buck-boost transformers are small, 1-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 are in compliance with NEC article 210.9, exception 1, when field connected as an autotransformer.

GE Buck Boost Transformer, Type QB Dry Encapsulated Enclosed Small Standard, Series: 9T51B, 120/240 VAC Primary, 16/32 VAC Secondary, 0.1 kVA, 60 Hz, 1 ph, Wire Lead, 6200 Frame, Wall Mount, Class A, NEMA 3R, 40 deg C, Silicon Steel Housing, 5.12 in W x 6.38 in H

• https://externalassets.unilogcorp.com/ASSETS/DOCUMENTS/ITEMS/EN/GE_9T51B0124_Specification_Sheet.pdf https://www.iesbuy.com//ASSETS/DOCUMENTS/ITEMS/EN/https://externalassets.unilogcorp.com/ASSETS/DOCUMENTS/ITEMS/EN/GE_9T51B0124_Specification_Sheet.pdf

• Core and coil in a NEMA 3R non-ventilated weatherproof enclosure
• Knockouts provided on back and bottom
• High grade silicon steel core
• Transformers are built to standard sound level of -3 dB
• Wiring compartment includes ground stud
• 55 deg C temperature rise
• K1-factor rated transformer
• Class A insulation system
• Mounting holes on side for easy access
• These GE transformers feature an encapsulated core and coil in a NEMA 3R non-ventilated weatherproof enclosure
• Electrostatically unshielded
• For bucking and boosting voltage
• 105 deg C insulation temperature
• Copper windings