Dual Operation Voltage-Sensitive Battery Switch (Automatic VSS + Parallel)

This advanced battery switch incorporates a Voltage Sensitive Switch (VSS) that automatically monitors and manages two battery banks for optimal charging. When your charging source (alternator or charger) is active, the VSS will charge the primary battery first, then automatically connect the second battery once the main reaches ~13.2V, allowing the alternator to efficiently charge both banks without manual intervention. In normal operation, it keeps the battery banks isolated to prevent one from draining the other. This dual operation switch also features a manual Emergency Parallel function: by turning a knob or pressing a control, you can link both batteries in parallel for a boost in starting power in emergency situations (e.g., if your start battery is low). The unit is built for 275A continuous load and up to 455A intermittent current, suitable for modern 12V or 24V dual-battery setups on larger boats. It has a rugged design with dual mounting options – it can be installed as a flush-mounted panel switch or surface-mounted – and the casing is sealed against sparks and moisture for marine safety. An indicator light (if included) can show when the VSS has connected the banks. By using this automatic VSR (Voltage Sensitive Relay/Switch), boat owners can ensure their house (auxiliary) battery is charged automatically once the start battery is full, without overcharging or manual switching. The device meets marine electrical standards (ISO 8846 / EN 28846) for ignition protection. In summary, this dual operation voltage-sensible battery switch simplifies battery management by combining smart charging technology with a manual override, ensuring you have power when you need it and efficient charging at all times.

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