Electrics & electronics

Many recreational boats use 12 V, while larger yachts and professional applications sometimes use 24 V. It is important that all loads, chargers, and fuses are compatible with the onboard voltage. Mixed systems (e.g., 24 V base + 12 V loads) function reliably when implemented with suitable converters (DC/DC), proper fusing, and a clear distribution structure.

Typical signs include voltage drops under load, slow or incomplete charging, frequent deep discharges, noticeably warm cables or connectors, and unstable loads (e.g., the radio briefly cuts out during startup). For a proper system design, battery capacity, charging power, load profile, and cable cross-sections must all be properly matched.

Common types include wet batteries, AGM/gel, and lithium systems. Differences lie, among other things, in charging characteristics, cycle life, permissible charging currents, and installation rules. Crucial: The charger must be compatible with the battery type (charging profile/charging voltages). For lithium batteries, a BMS, appropriate charging/safety parameters, and often a well-designed overall system (protection, sensors) are also important.

LEDs reduce power consumption, generate less heat, and are usually vibration-resistant. Ensure you use the correct sockets, correct polarity (for some systems), and a suitable light color for the application. For navigation lights, it is crucial that the light/unit is suitable or approved for the intended purpose (beam angle, visibility range, mounting).

Moisture, salt, vibration, and tensile forces are present on board. Marine-grade connector systems are generally more robust, better sealed, and more corrosion-resistant—this reduces contact issues, voltage drops, and failures. Strain relief, clean cable entries, and suitable seals are also important.

The basic tool is a multimeter (voltage/resistance/continuity). Also very helpful are a current clamp (for quick consumption checks), a battery tester or battery monitor (shunt), and simple 12-V/USB testers. These allow you to pinpoint voltage drops, poor contacts, and charging problems much more quickly.

The most important factors are sufficient wire gauge, short cable runs, clean crimped or screw connections, corrosion protection, appropriate fuses, and a stable ground connection. Common mistakes include cables that are too thin, loose terminals, poor ground points, or oxidized contacts (incorrect connectors or lack of moisture protection).

Basic rule: Select fuses based on the wiring (cross-section & routing) and the load—and place them as close as possible to the power source (battery/distribution panel). This protects the wiring from overload and reduces fire risks. For larger loads (e.g., inverters, bow thrusters, chargers), appropriately rated fuses/circuit breakers and a suitable main switch are recommended.

In a marine environment, professional crimp connections (using appropriate sleeves/connectors and good-quality pliers) are generally more reliable than soldered joints, because soldered joints can become problematic under vibration and tension. Heat-shrink tubing with adhesive, strain relief, and low-corrosion connectors also help.

Important factors include the installation location, a well-designed antenna setup, a stable power supply/fuse protection, and interfaces (e.g., NMEA) to the chartplotter/instruments. Depending on the device, programming, registration, and, if applicable, country-specific requirements may be relevant. Always plan radio/AIS as a system: device + antenna + cables/connectors + power + integration.

Standalone devices are quick to set up and independent. Integrated systems distribute position data to chartplotters, radio/AIS, or instruments and often benefit from an external antenna and seamless system integration. Key factors include interfaces, power supply, mounting position (line of sight to the sky), and which devices should receive/share data.

Relevant factors include standards/certification, battery life and replacement intervals, proper registration, and the installation location (quickly accessible in an emergency, securely mounted). Emergency transmitters are safety equipment—installation, testing, and maintenance should be carried out with particular care.

Simple tasks (e.g., changing light bulbs, replacing plugs) are often easily manageable. For fuses, main circuits, charging/shore power systems, and radio/emergency equipment, expert knowledge, proper documentation, and compliance with standards are essential. When in doubt, it’s advisable to have a professional inspection—especially for safety-critical systems.