Overview

The Hella Marine 007903001 is a 24 V relay with a 20 A rating and a five terminal blade connection layout for quick, secure wiring.

It is a practical way to switch a higher current load from a smaller helm switch, an automation output, or another low current control circuit. The changeover contact set lets you wire either normally open or normally closed behavior, which helps when you need a device to default to on or default to off when the coil is not energized.

Key features

• 24 V coil for 24 V onboard electrical systems
• 20 A rating for common accessory loads
• Single pole, changeover (SPDT) contact set for normally open or normally closed wiring
• Five blade terminals for standard push on electrical connectors
• Useful for keeping long control runs low current while the load wiring stays short and properly protected

Installation and setup

Mount the relay where wiring stays tidy and supported, typically inside a dry electrical space, behind a helm panel, or in a protected relay block. Use correctly sized female blade connectors that fit tightly, add strain relief so vibration does not work the terminals loose, and label the conductors so future troubleshooting is straightforward.

Electrical and system integration

Plan the circuit so the relay switches the load feed while your control side only powers the coil. Protect the load circuit with an appropriately sized fuse or breaker near the power source, and confirm the actual running current and startup surge of the device you are switching so the relay rating is not being pushed in real use.

Use cases on board

This relay is a good match for 24 V boats that need clean switching for accessories such as deck or spreader lights, ventilation blowers, small pumps, and other intermittent loads that fit within the current rating. It also works well when an electronics trigger or a control panel output needs to operate a separate power circuit without routing heavy current through the switchgear.