The Victron Autotransformer solves specific electrical compatibility issues by converting between different voltage systems. Available in 100A and 32A models (indicating feed-through current capacity), it handles up to 32A peak neutral current and 28A continuous current. Unlike step-up and step-down transformers, it is shares common primary and secondary windings between input and output.
What It Does
The Autotransformer performs four critical functions in electrical systems. It converts single-phase (European) 230V to split-phase 120/240V for powering equipment designed for North America. The Autotransformer also converts 120V sources into 120/240V for larger appliances. For systems with unbalanced loads, it redistributes power evenly across phases to prevent current or overload issues. Additionally, when paired with a compatible Victron inverter, it provides dynamic neutral-ground bonding when required for safety purposes.
The Autotransformer is essential when using North American equipment (120/240V) with European (230V) equipment, as it creates a center point neutral to match North American grid standards. You need an Autotransformer when your system has 240V appliances but you only have access to 120V shore power. It balances power across phases in split-phase systems experiencing current imbalances due to uneven loading.
Operation
The Autotransformer uses a toroidal core with copper windings that share a common section. This creates electromagnetic coupling while maintaining electrical continuity, allowing it to convert voltages without significant weight or size penalties. The unit includes a switchable neutral-ground bond relay that can be controlled remotely when paired with Victron inverters.
The Autotransformer requires proper sizing based on your maximum expected load. While it can handle up to 100A feed-through current (in the larger model), its conversion capacity differs depending on the specific voltage transformation required. The aluminum housing with powder-coat finish resists corrosion in marine environments, and the active cooling system maintains operation even in high ambient temperatures.
