The Functional Devices TIB100A is a housed, DIN rail-mountable 24VAC Class 2 power supply with a 96VA output rating, 120VAC primary input, and integrated circuit breaker overcurrent protection. Designed for HVAC control panels and building automation applications, the TIB100A snaps directly onto standard 35mm DIN rail — eliminating the foot-mount hardware, conduit hubs, and exposed wiring of traditional open-frame transformers. Pluggable terminal connections make wiring fast and servicing clean.
Best for: HVAC control panels, BAS panel builds, and any application requiring a compact, self-contained 24VAC Class 2 power supply that mounts directly to DIN rail without additional hardware.
The TIB100A is backed by Functional Devices' industry-leading 10-year warranty — the longest standard warranty in the RIB product line. Functional Devices reports a field failure rate of approximately 1 in 16,000 units, reflecting the reliability built into every product they manufacture.
Why the TIB100A — Housed DIN Rail Transformer vs. Open-Frame
Traditional 24VAC control transformers require foot-mounting to the panel back plate, conduit hubs for wire entry, and careful routing of exposed primary and secondary wiring. The TIB100A eliminates all of that. Its patent-pending housed design snaps directly onto 35mm DIN rail alongside other panel components, with pluggable screw terminals for both primary and secondary connections. The result is a cleaner, faster, and more professional panel build — particularly on projects where multiple panels are being built to the same layout. The integrated circuit breaker also eliminates the need for a separate fuse block on the primary side.
35mm DIN Rail Snap-On Mount
Mounts directly to standard 35mm x 7.5mm DIN rail with no additional hardware. Sits alongside contactors, relays, and other DIN rail components for a clean, organized panel layout. Compatible with Functional Devices ADIN35 DIN rail and ADIN35ES end stops (sold separately).
Integrated Circuit Breaker
Built-in circuit breaker provides overcurrent protection on the primary side — eliminating the need for a separate fuse block or disconnect. Resettable without replacing a fuse, which reduces service time in the field. Protects both the transformer and connected 24VAC control circuits.
Pluggable Terminal Connections
Both primary (120VAC) and secondary (24VAC) connections use pluggable screw-type terminals. Terminals can be disconnected from the unit for wiring before installation, then plugged in — speeding up panel build time and simplifying troubleshooting or replacement without disturbing connected wiring.
UL Class 2 Listed
Listed to UL5085-3 as a Class 2 power supply and UL508 for industrial control equipment. Also carries C-UL (Canadian), CE (European), and RoHS approvals. The Class 2 rating limits output power to levels that do not require additional overcurrent protection on secondary wiring under NEC Article 725.
Installation Note — Primary Terminal Wiring
The 120VAC primary side has three terminals, marked Neutral, [No Connect], and 120 Vac (Line). Connect Line (120VAC hot) to the 120 Vac terminal and connect Neutral to the Neutral terminal. The center [No Connect] terminal is not used and should be left unwired. On the 24VAC secondary side, Neutral is in phase with Com. Output derating may exceed 20% at elevated ambient temperatures or due to heat buildup in enclosed panels — account for this when sizing for loads near the 96VA rating.
| Specification | Value |
|---|---|
| Part Number | TIB100A |
| VA Rating | 96 VA |
| Primary Input | 120 VAC, 50/60 Hz |
| Secondary Output | 24 VAC |
| Primary Terminals | Neutral, [No Connect] (unused center), 120 Vac Line |
| Secondary Neutral | In phase with Com |
| Overcurrent Protection | Integrated Circuit Breaker |
| Mounting | 35mm x 7.5mm DIN Rail (snap-on) |
| Dimensions | 4.315” x 3.112” x 3.255” |
| Max Ambient Temperature | 40°C (104°F) |
| Approvals | Class 2 UL5085-3 Listed, UL508, C-UL, CE, RoHS |
| Origin | Made of US and non-US parts |
| Warranty | 10 Years |
| Accessories | ADIN35 (DIN Rail), ADIN35ES (End Stops) — sold separately |
| Patent Status | Patent Pending |
HVAC Control Panels
24VAC Class 2 supply for BAS controllers, relays, actuators, and sensors mounted on DIN rail in the same panel
Building Automation Systems
Powers 24VAC BAS field controllers, input/output modules, and networked devices from a single Class 2 source
Relay Panel Power Supply
Provides isolated 24VAC supply for RIB relay panels and Functional Devices control assemblies
VAV / Zone Control Panels
Compact DIN rail footprint fits neatly in smaller zone control enclosures alongside VAV controllers and actuators
Retrofit Panel Builds
Replaces foot-mount open-frame transformers in retrofits where DIN rail organization and clean wiring are priorities
Multi-Panel Projects
Consistent, repeatable DIN rail placement makes it ideal for projects where multiple identical panels are being built
- VA Rating:
- 100 VA
- Primary Voltage:
- 120 VAC
- Secondary Voltage:
- 24 VAC
