Functional Devices Relays & Fan Sequencers

Functional Devices RIB® Relays & Fan Sequencers

Functional Devices has been at the forefront of building automation and HVAC control since 1969, and nowhere is that expertise more apparent than in their flagship RIB® (Relay in a Box®) product line. As the original manufacturer of the RIB® Relay, Functional Devices has been making building automation devices and energy-saving controls in the USA since 1969. Their Relays & Fan Sequencers represent decades of refinement in a product that HVAC technicians and building automation engineers rely on every day.

What Makes RIB® Relays Stand Out

Functional Devices' RIB® (Relay-In-a-Box®) line is built for versatility — these compact, pre-wired relays reduce installation time, simplify wiring, and adapt easily across a wide range of applications. Rather than sourcing a relay, socket, mounting rail, and enclosure separately, RIB units come mounted and pre-wired in a housing, saving the installer the time, trouble, and expense of buying separate components and assembling them on the job or at the shop.

RIB® relays serve as the interface between building automation system (BAS) binary outputs and line-voltage HVAC load circuits, keeping the controller electrically isolated from the loads it switches. This makes them an essential component anywhere a low-voltage control signal must safely command a high-current fan, pump, or motor circuit.

Broad Voltage Compatibility & Configuration Options

Broad voltage compatibility, multiple contact configurations, and proven reliability make RIB® relays the kind of components technicians and engineers rely on when conditions change in the field. The lineup spans a wide range of switching requirements:

• The RIBU1C — a 10A SPDT relay with a universal 10–30 VAC/DC or 120 VAC coil — is a widely specified general-purpose relay suited for light-duty switching such as damper actuators and pilot duty loads.
• The RIB2401B (20A SPDT, 24 VAC/DC or 120 VAC coil) handles fan coil unit control and rooftop unit enable circuits across most configurations in commercial construction.
• For higher-current or dual-circuit loads, the RIB24P30 offers 30A DPDT switching with a 24 VAC/DC coil.
• The RIBH1C is a heavy-duty enclosed pilot relay engineered for building automation and HVAC industrial control circuits, featuring a unique dual-coil input design capable of accepting 10–30 VAC/DC or 208–277 VAC for multi-voltage field applications.

Built-In Features for Faster, Smarter Installations

Functional Devices engineers practical advantages directly into every RIB® unit. Many models feature a mechanical life expectancy of 10 million cycles for long-term reliability in demanding HVAC/R control applications, along with an integrated LED status indicator that allows for immediate troubleshooting of the control signal. Mounting flexibility is also a hallmark — RIBs are available in surface, DIN-rail, or snap-track options to fit any panel layout.

Every unit is tested before it leaves the production floor in Indiana to ensure customers get the product quality they have come to expect. Because RIB® relays are UL Listed as complete assemblies, they clear inspection without requiring field reassembly. Whether you are staging multiple rooftop units, sequencing fans across a large commercial facility, or interfacing a low-voltage thermostat with a line-voltage motor, Functional Devices' Relays & Fan Sequencers deliver the reliability and flexibility the job demands.