AC Changeover Switch

Transfer Switches for Shore Power, Generator, and Inverter

Modern onboard electrical systems often feature multiple power sources such as shore power, generators, and inverters. To ensure these power sources can be used safely and in compliance with standards, a reliable transfer switch is required. It prevents the simultaneous feeding of multiple AC power sources into the onboard electrical system, thereby protecting people, consumers, and electrical installations from damage.

Our transfer switches enable safe and automatic switching between different AC power sources, ensuring an uninterrupted and reliable power supply on board.

Safe Isolation of Multiple Power Sources

When shore power, a generator, or an inverter are used together in an onboard electrical system, the individual power sources must be all-pole isolated from each other. This is crucial not only for safety but also for compliance with applicable maritime standards and regulations.

The transfer switches automatically select the available power source and reliably prevent:

• Parallel connection of multiple power sources

• Backfeeding into the onboard electrical system

• Short circuits due to phase shifts

• Damage to generators, inverters, and consumers

• Dangerous operating conditions in the AC onboard electrical system

Automatic Grid Switching for Maximum Convenience

The automatic transfer switches of the LAU series continuously monitor the input voltage of the connected power sources. Switching only occurs when the respective power source meets the defined voltage and time criteria.

This ensures, for example, that generators are only switched on once they have fully started up and their nominal voltage has been stably reached. This protects sensitive consumers and ensures safe operation of the entire AC network.

Smart Control via the P-Bus System

The transfer switches of the LAU series are prepared for integration into the philippi P-Bus system. In conjunction with the PSM or PSL system monitors, important parameters can be conveniently configured and monitored.

These include, among others:

• Switching delay times

• Voltage limits

• Prioritization of individual power sources

• Status display of the active power source

• Monitoring of the AC onboard electrical system

This creates a fully integrated energy management system for modern boats and yachts.

Protection Against Unnecessary Battery Discharge

An additional output circuit allows for the automatic shutdown of selected consumers in inverter operation. For example, chargers, water heaters, or other energy-intensive consumers can be specifically deactivated.

This protects the batteries from unnecessary discharge and optimizes the use of the available energy reserve on board.

Standard-Compliant AC Installation On Board

When retrofitting or newly installing a transfer switch, it should be ensured that the connected circuits are protected by suitable RCBO circuit breakers (FI/LS combinations). This guarantees protection against fault currents, overload, and short circuit, and complies with the requirements of modern onboard electrical systems.

Your Advantages at a Glance

• Automatic switching between shore power, generator, and inverter

• Safe isolation of multiple AC power sources

• Protection against backfeeding and short circuits

• Delayed switching for maximum operational safety

• Intelligent voltage monitoring of all power sources

• Integration into the P-Bus system possible

• Configuration via PSM and PSL system monitors

• Protection against unnecessary battery discharge

• Ideal for boats, yachts, and expedition vehicles

• Standard-compliant and safe AC onboard electrical system installation

With the automatic transfer switches of the LAU series, you create a safe, convenient, and professional energy distribution between shore power connection, generator, and inverter – for maximum supply security on every trip.