SDI Series Flow Sensor

The Data Industrial SDI Series insert flow sensors from Badger Meter offer accurate liquid flow measurement in closed pipe systems in an easy-to-install economical package. Impeller sensors offer a quick response to changes in flow rate and are well suited to flow control and batch-type applications in addition to flow monitoring. The four-bladed impeller design is rugged, non-fouling, and does not require custom calibration. Coupled
with the proprietary patented digital detection circuit, the sensor measures flow from under 0.5 ft/sec (0.15 m/sec) to more than 20 ft/sec (6.1 m/sec) regardless of the conductivity or turbidity of the liquid. The standard frequency output produces a low impedance square wave signal proportional to the flow rate that may be transmitted up to 2000 ft (610 m) without amplification. The SDI Series includes:

  • Single-direction powered insert with raw, scaled pulse, and analog output
  • Bidirectional powered insert with analog and scaled pulse output
  • Battery-powered insert with a local or remote display and scaled pulse output


SDI insert style flow sensors are intended for general clean liquid flow measurement applications. They are available in either brass or stainless steel construction.




More Details


These insert-style sensors are intended for direct installation into pipelines through a 1 in. (25 mm) tap. The pipeline must be out of service and not under pressure at the time of installation. For any pipeline that is in service at the time of installation or cannot be de-pressurized and drained for service, the SDI hot tap model equipped with isolation valves is recommended. Three different stem lengths in both the direct insert and hot tap versions accommodate pipe diameters 1-1/2…36 in. (38…914 mm) depending on the pipe material and tapping methods. Larger sizes usually require the use of hot tap models. In pipe sections with at least 10 diameters of straight pipe upstream of the sensor and 5 diameters of straight pipe downstream, accuracies of ±1% of the rate may be achieved when the flow sensor is installed at the correct insertion depth and properly aligned

How they work