The Badger Meter SDI series impeller flow sensors offer a cost-effective and easy-to-install solution for liquid flow measurement in closed pipe systems. Designed for insertion or hot tap installations, they provide a quick response to flow rate changes, making them well-suited for flow control, batch applications, and general flow monitoring .

The SDI series measures flow rates from under 0.3 ft/sec to over 20 ft/sec. A proprietary digital detection circuit allows the meter to achieve accuracies of up to ±1%, regardless of the liquid's conductivity or turbidity. The sensor features a rugged, four-bladed, non-fouling impeller that does not require custom calibration .

The sensors are available in both brass and stainless steel construction for direct insertion into pipes via a 1" tap. Hot tap versions, constructed of 316 stainless steel, feature an isolation valve for installation or removal from a pressurized pipeline without system shutdown, and are rated for service up to 1000 psi and 180°F. Options include bidirectional flow metering, battery-powered electronics, and various outputs and materials, allowing customization for nearly any application .