Functional Devices
Representative Photo, actual item may vary
Functional Devices PSMN40A24DS DIN Rail Mount Power Supply 120VAC to 24VDC 1 Amp Isolated
Functional Devices PSMN24DAS Non-Isolated Linear DC Power Supply 24VAC to 1.5-28VDC 300mA Track Mount
Functional Devices PSM2RB10 UPS Power Control Center 10A 120VAC 2 Outlet DIN Rail Mount
Functional Devices PSM24A24DAS Track Mount 24VAC to 24VDC Power Supply 300mA
Functional Devices PSM20A12DAS Track Mount Isolated Linear DC Power Supply 24VAC 300mA Adjustable
Functional Devices PSH850-UPS-STAT Enclosed UPS Interface Board with 850VA UPS and Status Monitoring
Functional Devices PSH75AB10 75VA Enclosed Power Supply 120/208/240V to 24VAC UL Class II with 10A Breaker
Representative Photo, actual item may vary
Functional Devices PSH75A 75VA Multi-Tap Power Supply Transformer 24VAC UL Class 2
Functional Devices PSH600-UPS 600VA UPS Backup Power Control Center with 10A Circuit Breaker
Functional Devices PSH500A-LVC Enclosed 500VA Power Supply with 5 Class 2 Outputs
Functional Devices PSH500A 500VA Enclosed Power Supply with Five 100VA Class 2 Outputs
Functional Devices PSH300A-LVC 300VA Power Supply with Three 24VAC Class 2 Outputs
Functional Devices RIBHX24BF Current Switch and Relay Combination 0.25-20 Amp SPST 24VAC/DC
Functional Devices PSH300A Enclosed Power Supply 120/240/277/480V to 24VAC 3-100VA UL Class 2
Functional Devices PSH24DWB10 Enclosed Power Supply to with Breaker Transformers - 120VAC 24VDC 2.5A 10A
Functional Devices PSH100AW 100VA 120V to 24V Transformer UL Class 2 Power Supply
Functional Devices PSH100AB10 Enclosed Power Supply to with Breaker Transformers - 100VA 120V 24VAC 10A
Functional Devices PSH100A100AB10 Dual Power Supply Transformer 120V-24VAC 100VA with Circuit Breaker
Functional Devices PSH100A Enclosed 100VA UL Class 2 Power Supply 120VAC to 24VAC
Functional Devices RIBMNLB-4 AHU Fan Safety Alarm Logic Circuit 4-Input Track Mount
Functional Devices RIBMNLB-2 AHU Fan Safety Alarm Logic Board 24V AC/DC Track Mount
Functional Devices RIBMN24S-4T Four Pilot Relays 15A SPST Override 24V Track Mount
Functional Devices RIBMN24Q4C-PX 4-Stage Relay Module 0-10VDC Control 24VAC/DC
Functional Devices RIBMN24C-4T Four Pilot Relays 15A SPDT 24V Track Mount Panel Relay
Representative Photo, actual item may vary
Functional Devices TR175VA003 Transformer 175VA 120V to 24VAC with Thermal Fuse
Functional Devices TR150VA008 Control Transformer 150VA 208-480V Primary 120V Secondary
Functional Devices TR100VA009US Transformer 96VA 120/208/240/277/480-24V Class 2 UL Listed DIN Rail
Functional Devices TR100VA004 Transformer 100VA Multi-Voltage 120/240/277/480V to 24V Dual Hub
Functional Devices TR100VA001 Transformer 100VA 120V to 24V Single Hub Class 2 UL Listed
Functional Devices RIBXLSRA Current Sensor and Relay Combination with Adjustable Solid-Core AC Sensor
Functional Devices RIBXLSA Current Sensor and Relay 10 Amp SPST 10-30Vac/dc Adjustable
Functional Devices RIBXLCRA Enclosed 10 Amp SPDT Relay with Adjustable Current Switch 1.25-150A
Functional Devices RIBXLCF Current Switch and Relay Combination 10 Amp SPDT Fixed 0.5-10A
Functional Devices RIBXLCA Current Switch Relay 0.5-10 Amp Adjustable SPDT 10A
Functional Devices RIBXKTV5-10 Solid Core Current Transducer 0-10 Amp 0-5 VDC Output
Functional Devices RIBXKF Enclosed Fixed Current Sensor 0.25-150 Amp Pre-wired Output
Functional Devices RIBXGTV5 Enclosed Split-Core Multi-Range AC Current Transducer 0-5VDC
Functional Devices RIBU1CW Enclosed Pilot Relay 15 Amp SPDT 10-30 Vac/dc/120 Vac Coil
Functional Devices TR40VA004 Transformer 40VA 277/240/208/120V to 24VAC Multi-Mount
Functional Devices TR40VA003 Transformer 40VA 24V Primary 24V Secondary Class 2
Functional Devices TR20VA004 20VA Multi-Tap Control Transformer 277/240/208/120V to 24V
About Functional Devices
Functional Devices has built a strong reputation as a leading American designer and manufacturer of control devices for the HVAC, building controls, and energy management industries. Founded on the principle that reliable, precision-engineered components are the backbone of any well-functioning building system, Functional Devices has become a go-to name for contractors, engineers, and facilities managers who demand consistency and quality from their electrical control hardware.
What sets Functional Devices apart is their commitment to domestic manufacturing. Every product is designed and built in the United States, ensuring tight quality control and shorter lead times compared to overseas alternatives. Their catalog of over 200 products covers the critical electrical and control components that keep commercial and residential HVAC systems running safely and efficiently.
Transformers for HVAC and Building Controls
One of Functional Devices' most recognized product lines is their lineup of Transformers. These step-down control transformers are engineered specifically for HVAC applications, converting line voltage down to the 24VAC signal voltage that thermostats, zone valves, and control boards depend on. Functional Devices transformers are designed with built-in overcurrent protection and a range of VA ratings to match virtually any residential or commercial application.
Relays, Fan Sequencers & Automation Controls
Perhaps the product line Functional Devices is best known for is their Relays & Fan Sequencers. Their iconic RIB® (Relay in a Box) series revolutionized the industry by packaging a fully enclosed, plug-in relay into a compact, universal-mount enclosure — eliminating the need for a separate panel or DIN rail in many installations. Fan sequencers from Functional Devices help stage multi-speed blower motors and electric heating elements efficiently, reducing electrical stress and improving system longevity.
Motor & Electrical Parts and Accessories
Beyond their flagship lines, Functional Devices also offers a selection of Motor & Electrical Parts & Accessories that complement their control systems. These components are designed to integrate seamlessly with Functional Devices transformers and relays, making it straightforward to build or service a complete control circuit without sourcing parts from multiple vendors.
Accessory Power Relays
For applications requiring switched power control, Functional Devices produces Accessory Power Relays suited to a variety of load types. These relays provide dependable switching action for auxiliary equipment loads, and their robust construction reflects the same durability standards applied across the entire Functional Devices product range.
Why Choose Functional Devices?
- American-designed and manufactured for consistent quality and reliability
- Extensive product range covering transformers, relays, sequencers, and accessories
- Industry-leading RIB® relay platform with universal mounting flexibility
- Products engineered specifically for HVAC, building automation, and energy management systems
- Trusted by HVAC contractors, electrical engineers, and facilities professionals nationwide