Functional Devices TR20VA007 277V to 24V 20VA Control Transformer Foot and Hub Mount

The Functional Devices TR20VA007 is a 20 VA Class 2 control transformer designed for building automation, HVAC, and temperature control applications. It steps down a 277V AC primary voltage to a 24V AC secondary output, making it well-suited for commercial lighting circuits and other 277V branch circuits commonly found in commercial and industrial buildings.

Part of the Functional Devices RIB TR Series, this unit features split-bobbin construction for reliable electrical isolation between primary and secondary windings. Overcurrent protection is handled through inherent current limiting — no external fuse or breaker required on the secondary. The compact housing supports both foot mount and single threaded hub (0.5" NPT) mount configurations, providing installation flexibility in enclosures, junction boxes, or direct surface mounting.

Key Features:

• Primary voltage: 277V AC | Secondary voltage: 24V AC
• VA rating: 20 VA
• Frequency: 50/60 Hz
• Mounting: Foot and single threaded hub (0.5" NPT)
• Overcurrent protection: Inherently limited (Class 2)
• Construction: Split-bobbin for enhanced isolation
• Operating temperature: -30°F to 140°F
• MTBF: 100,000 hours at 77°F
• Wire leads: 8" typical with 0.5" strip
• Approvals: Class 2 UL5085-3 Listed, C-UL, CE, RoHS
• Listed for use in US and Canada

The TR20VA007 is an ideal replacement or new-installation transformer wherever a compact, UL-listed 277V-to-24V step-down is needed for control circuits in commercial HVAC and building automation systems.