Functional Devices RIB2421C Relay

The Functional Devices RIB2421C is a contractor-grade enclosed pilot relay designed for seamless integration into building automation systems (BAS) and HVACR control circuits. This Relay in a Box (RIB) features a single pole double throw (SPDT) configuration with a 10 Amp contact rating, making it a reliable solution for switching line voltage loads such as fans, pumps, and lighting from a low-voltage controller. The versatile multi-voltage coil accepts 24 VAC/DC or 120-277 VAC, eliminating the need to carry multiple parts on your truck for different job site requirements.

Housed in a compact, NEMA 1 plenum-rated enclosure, the RIB2421C includes a 1/2" NPT nipple for direct mounting to a standard conduit knockout, significantly reducing installation time in the field. The unit includes an integrated LED indicator to provide instant visual confirmation of the relay status, which is essential for rapid troubleshooting in complex control loops. Built with 16-inch 600V pre-wired leads, this relay is UL Listed for UL916 Energy Management and UL864 Fire Alarm standards, ensuring compliance across various commercial and residential applications.

• Universal Coil Compatibility: Operates on both 24 VAC/DC and 120-277 VAC, streamlining your inventory and simplifying field replacements.
• Plenum-Rated NEMA 1 Housing: Pre-wired and ready for installation in air-handling spaces without additional mounting accessories or junction boxes.
• High-Quality Contacts: Rated for 10 million mechanical cycles to ensure long-term durability in pilot duty and general use applications.
• Fast Mounting: The 1/2" threaded hub and color-coded wires allow for secure, error-free installation directly into equipment panels or conduit.

Can the RIB2421C be used to control small motors?
Yes, the contacts are rated for 1/2 HP at 125 VAC and 1 HP at 250 VAC, making it suitable for lower-horsepower motor control in commercial HVAC systems.

What does the LED indicator signify?
The LED is wired in parallel with the coil; when the LED is on, the coil is energized and the SPDT relay has switched positions.

Is this relay suitable for fire-alarm systems?
The RIB2421C is UL864 listed, which allows it to be used in fire alarm service as a pilot relay for non-critical control functions.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.