Hybrid Ultrasonic Flowmeter

accQrateThe accQrate can measure fluid flow in virtually any fluid in which sound waves can travel. The accQrate is considered "hybrid" because they can measure fluid flow using either the Doppler or Transit Time methods. The accQrate ultrasonic sound transducers are clamped to the outside of the pipe wall and include no moving parts. This method of flow measurement is safe, non-intrusive, and very easy to service.

The Doppler measurement method requires particles to be present in the flow stream to "reflect" the sound waves. The meter may be operated in the Doppler mode when the fluid contains 0.02% to 15% (200 to 150,000 ppm) of particles.

The Transit Time measurement method requires relatively "clean" fluid to enable the sound to complete their circuit. The meter may be operated in the Transit Time mode when the fluid contains 0% to 10% (0 to 100,000 ppm) of particles. To allow for changes in the fluid's particle count, the S2 monitors the signal gain and employs an Automatic Gain Control (AGC) algorithm that periodically adjusts the gain to maintain the optimum power level.

The speed at which sound travels in the fluid must be known. The factory will configure the meter for a known fluid during the initial configuration. The accQrate includes a 5-button user interface and remote PC software that can be used to configure the meter. Many common fluids are listed in the software and can be selected directly from the menu. Provided the speed of sound is known, custom "unknown" fluids can be input manually by the user. A list of various fluids and their sound speeds are provided in the user manual.



Teledyne ISCO Water & Wastewater Product GuideBrochure
accQrate Clamp-On Flowmeter DataSheetDatasheet (Legacy)
accQrate Hybrid Ultrasonic Flow Meter ManualUser Manual (Legacy)


When you purchase instruments from Teledyne ISCO, you not only receive innovative, high quality products, you also receive excellent customer service and product support. Your initial purchase is only the beginning of Teledyne ISCO's ongoing commitment to their customers.



​Dimensions (H x W x D): ​21" x 17" x 9 1/2"
​Weight (Dry): ​24 lbs. (10.9 kg)
​Pipe Linear Materials:

​Most plastic liners

​Pipe Materials: ​Most metal and plastic pipes
​Measuring Principle: ​Hybrid. User-selectable Doppler or Transit Time operating modes

​Fluid Types:

​Virtually any acoustically conductive fluid. Transit time mode from 0% to 10% (0 to 100,000 ppm) particulate. Doppler mode from 0.02% to 15% (200 to 150,000 ppm) of 50 micron particulate.
​Fluid Velocity Range: ​0.25 to 30 feet per second (0.07 to 9 meters per second)
​Nominal Pipe Sizes: ​2.0 inch - 100 inch (63mm - 2500mm)

​SPU (Signal Processing Unit) ​


​NEMA 4X (IP66), Powder coated aluminum, SS clamps and hardware.

Dimensions: 11.00H x 8.60W x 5.00D inches (279H x 218W x 127D mm)

Weight: 9.5 lb. (4.3 kg.)


​Wall, pipe (vertical or horizontal) or panel mounting. Hardware included.

Panel opening: 10.63H x 8.10W inches (270H x 206W mm)

Panel Depth. Rear: 2.78 inches (71 mm), Front: 2.18 inches (55 mm)

​Power Requirements: ​95 - 264 VAC 50/60Hz or 15 - 30 VDC; 30 watts maximum
​Operating Temperature:

​14°F to 140°F (-10° to 60°C)

Storage: -40°F to 158°F (-40° to 70°C)


​320 x 240 pixel QVGA backlit LCD, UV resistant.

Simultaneous Rate and Total: 10 digit maximum + exponent to E+32 Decimal point factor configured.

​Display Languages: ​English, Spanish, French, or German factory configured
​Keypad: ​Two-button positive action tactile switch keyboard
​Display Volume Units:

​Factory configured Rate and Total display units in: U.S. Gallons, ounces, barrels (US liquid), barrels (US oil), cubic feet, acre, feet, Imperial (British) gallons, liter, cubic meter, or user defined "custom" units.

Rate display in feet or meters per second.

​Display Time Units: ​Factory configured for seconds, minutes, hours, days.
​Display/Output Update Time: ​Factory configured for 1.0 seconds.
​Flow Rate Display Averaging: ​Factory configured for 5.0 seconds.

​Isolated 4 - 20 mA output -- factory scaled at 0 to 30 ft./s

0 - 1000Hz Pulse output -- factory scaled at 0 to 30 ft./s

​Data Logging: ​Data/time stamped flow rate and flow total data in FAT32 file format, easily imported into Excel. Factory configured to trigger at 3 minutes time intervals. Over 500,000 log events possible with included 3MB SD Card.

Clamp-On Transducers ​


NEMA 6P (IP67), Nickel plated aluminum, SS clamps & hardware.

Dimensions: 3.12H x 2.95W x 1.60D in. (79H x 75W x 41D mm)

Weight (excluding cable): 0.8 lb. (0.4 kg.) each


​Shielded coaxial RG/U Type:59. PVC jacket, black. RoHS Compliant.

Standard Length: 10 ft. (3m)

Optional lengths available: 25 ft. (7m), 50 ft. (15m), 100 ft. (30m)

​Pipe Surface Temperature: ​-20° to 300°F (-34° to 150°C)

​For a full list of product specifications, s​ee the datasheet.



Standard Features

  • Selectable Doppler or Transit Time operating mode
  • Custom quality metric algorithms and DSP technology ensures reliable, high accuracy measurements
  • Quick and easy clamp-on transducer installation. Proprietary AGC (Automatic Gain Control) algorithm eliminates manual adjustment.
  • Tamper Resistant 2-button user interface
  • Factory configured for easy installation
  • High quality 320 x 240 pixel QVGA backlit LCD
  • Data logging to standard SD Card format. Factory configured to three minute time interval triggers. Logs time, date, flow rate, and total flow values. 500,000 events with included 32 MB SD Card.
  • Isolated 4 - 20 mA output -- factory configured
  • 0 - 1000 Hz Pulse output -- factory configured
  • Optional -- Computer connection via RS-232, RS-485, USB, Ethernet. Permits remote access and control of all functions including real-time display, system configuration, data logging, remote data capture and process control functions. Software permits remote internet access through local network set-up.


  • Sewage
  • Wastewater
  • Pulp & Paper Slurries
  • DI water
  • Discharge water
  • Caustics
  • Chemical Slurries
  • Ground water
  • Food and Beverages
  • Petrochemical
  • Any sound conducting liquid