Overview

The Hella Marine 007794911 is a 12V Mini ISO relay for switching higher-current circuits like driving lights and fog lights from a low-current helm or dash switch. It is rated for 40A continuous load and uses an SPDT/Form C contact set with 5 terminals, so it can run a simple on/off circuit or a changeover circuit where one feed is switched between two outputs.

This style of relay is commonly used on boats to keep the high-current wiring run short and protected, while the switch at the helm only carries the coil current. The included weatherproof cover and mounting bracket make it easier to mount the relay in places that see moisture and vibration, such as under a console, inside a locker, or near an electrical distribution area.

Key features

• 12V DC coil with 40A continuous switching capacity
• SPDT/Form C changeover contacts for normally open or normally closed wiring
• 5-pin Mini ISO footprint to match common relay sockets and harnesses
• Weatherproof cover to shield the relay body and terminals from damp air and spray
• Mounting bracket for securing the relay to a bulkhead or panel
• Resistor coil suppression to help tame voltage spikes on the control side

What’s included

• Mini ISO relay (12V, 40A, SPDT/Form C)
• Weatherproof cover
• Mounting bracket

Installation and wiring notes

Mount the relay where it stays accessible for troubleshooting and where the cover can be seated properly over the terminals. In most lighting installs, the relay is placed close to the fused power feed or close to the load to keep higher-current cable runs short and tidy.

Size the fuse, wire, and terminals to the actual load, and use properly crimped connections that are sealed for the marine environment. After wiring, check for heat at the terminals under load, then secure the harness so vibration does not work the connections loose over time.

Compatibility and fit

This relay is for 12V DC systems. It uses a 5-terminal Mini ISO layout, so it pairs with standard 5-pin Mini ISO sockets and pre-wired pigtails. If your circuit only needs a basic on/off function, it can be wired using the common and normally open terminals while leaving the changeover terminal unused.

Use on board

It is a practical choice for auxiliary driving lights, fog lights, spreader lights, and other add-on lighting where you want full battery-fed current at the load without routing that current through the helm switch. It also helps when you are building a cleaner relay panel for refits, repowers, or new electronics and lighting additions.