Functional Devices Accessory Power Relay

Functional Devices Accessory Power Relays: RIB® Engineering Meets Reliable Switching

When it comes to accessory power relays, few names carry the engineering credibility and field-proven track record of Functional Devices. Founded in 1969, Functional Devices has spent decades designing and manufacturing quality electronic devices right here in the United States. In the accessory power relay segment, that long history translates into products built to switch loads reliably in demanding environments — from HVAC equipment rooms to building automation panels.

The RIB® Advantage in Power Relay Applications

Functional Devices is the original manufacturer of the RIB® (Relay in a Box®) relay — a product line that has become a benchmark for enclosed relay design in the controls industry. The RIB® platform brings a self-contained, compact form factor to accessory power relay applications, simplifying installation while maintaining robust electrical performance. Their relay products are rigorously tested for unmatched reliability, with fewer than 1 in 16,000 failing in the field — a statistic that speaks volumes for mission-critical switching tasks where a failed relay can mean a failed system.

Functional Devices offers enclosed pilot relays such as the RIB21CDC, featuring Class 2 dry contact input, 120–277 Vac power handling, and a 10A SPDT switching configuration — making them well-suited as accessory power relays in a wide range of control architectures. These enclosed designs protect internal contacts from dust, moisture, and vibration, extending service life in real-world installations.

Built for Building Controls & Energy Management

Functional Devices designs and manufactures devices used for building controls, energy management, HVAC, lighting controls, energy savings, and wireless industries throughout the United States. Their accessory power relays fit naturally into these ecosystems, serving as the switching backbone that enables low-voltage control signals to actuate higher-power loads — fans, pumps, damper actuators, and auxiliary equipment circuits.

Current product offerings include RIB relays alongside current sensors, power control modules, enclosures, power supplies, and transformers — meaning a Functional Devices accessory power relay can slot into a complete, cohesive control solution rather than being an isolated component. This systems-oriented approach is a key reason engineers and technicians reach for Functional Devices relays when specifying accessory power control.

Warranty & Quality You Can Count On

Functional Devices backs their relay lineup with an industry-leading 10-year warranty, providing confidence and peace of mind in every box. For accessory power relay applications where longevity and low maintenance are priorities, that warranty commitment sets Functional Devices apart from many competing brands. Combined with their Made in USA manufacturing heritage and decades of controls industry expertise, these relays represent a dependable choice for professionals who cannot afford switching failures in the field.

Browse the full selection of Functional Devices accessory power relays, explore the complete Functional Devices brand catalog, or view all available accessory power relays to compare options across top manufacturers.