Mono-Stable DC Power Relay

This mono-stable DC power relay is a heavy-duty switching device built for high-current applications in agricultural, construction, and transportation equipment. Unlike bi-stable latching designs, a mono-stable relay closes its contacts only while its coil is energized, returning to the open state the moment coil power is removed. This behavior makes the relay well suited to applications where the connected load should automatically de-energize on control-power failure, including safety-critical circuits, emergency-off systems, and interlocked machinery.

Available in 100, 200, and 300 amp continuous current ratings with 12 VDC and 24 VDC coil options, this mono-stable relay features an environmentally sealed IP67 contact system and a shock- and vibration-resistant enclosure built to withstand harsh operating conditions. The sealed design keeps fluids, cleaning agents, and dust from degrading contact performance over the relay's service life. Low contact drop supports stable voltage delivery to critical downstream components, and a compact housing allows installation in tight engine compartments, battery boxes, and switchgear panels.

Bottom-mount and bracket-mount options accommodate a range of installation constraints, and optional hardware kits and diode-suppression modules simplify wiring while adding reverse-polarity protection to the driving control circuit. Typical applications for this mono-stable DC power relay include starter motor solenoids, alternator field control, electric-vehicle power management, industrial DC contactor duty, marine main power switching, and telecommunications DC power distribution.