The SV-12-4 is a Solenoid Operated Diesel Fuel Shutoff Valve for a 12 volt system. This model has a 1/4 NPT inlet and outlet, and an optional 1/4 inch (6 mm) orifice. The SV-4 valves open against 15 psi (103 kPa) [1.03 bar] inlet pressure. This valve is recommended where greater flow is required, and only static head or low transfer pump pressures are encountered. The SV-12-4 valve is a normally closed valve that opens when current is supplied from the battery through a magnetic switch. Temperature, Level, or Pressure Swichgage instruments installed on the engine and pump or compressor trip the magnetic switch, breaking the circuit from the battery, which closes the valve and stops the engine.