Simarine Combo Shunt Modules (SC303 / SC503)The Simarine SC303 and SC503 modules measure voltage, current, and temperature to give a complete overview of your battery system. They also support additional inputs such as tank levels and external sensors, making them ideal for more advanced RV, marine, or off grid installations. Built for seamless integration with Simarine systems, they deliver accurate, real time data to help you monitor and manage your power usage effectively.