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Flow and Level Measurement Wastewater Applications Guide

Download the Flow and Level Measurement Wastewater Applications Guide

New Products

SE16B ultrasonic transducers

TTFM 6.1 Transit Time Flow Meter

  • Enhanced Performance
  • Wide Range of Applications
  • Easy to Install and Configure
  • Non-Contacting Clamp-on Ultrasonic Transducers
  • Works on a Large Variety of Pipe Materials and Sizes
  • Large Backlit Flow Rate Display and Totalizer
  • Isolated 4-20mA Output
  • 2 Programmable Control Relays
  • Optional MODBUS® RTU or HART Output
  • Application Optimization Available
  • 128MB Data Logger


Accurately measure the flow rate of relatively clean, non-aerated liquids like potable water, raw water, cooling water, de-ionized or reverse-osmosis water, oils and chemicals in full pipes. Ultrasonic transducers mount on the outside of a pipe without shutting down flow. Flow rate is displayed on the large, backlit display, along with total volume, signal strength, relay status, and other diagnostic values. Use the built-in control relays as flow alarms or volume totalization. Connect the isolated 4-20mA output to PLC's or controllers. A 128MB data logger is standard, capable of capturing up to 26 million data points. Optional MODBUS RTU via RS-485 available for connection to automation systems.

The TTFM 6.1 works on a wide range of pipe sizes and materials including carbon steel, stainless steel, ductile iron, concrete lined ductile iron, cast iron, PVC, PVDF, fiberglass, copper, brass, aluminum and pipes with bonded liners including epoxy, rubber and Teflon.

The TTFM 6.1 Transit Time Flow Meter operates by measuring the “transit time” or “time of flight” for ultrasonic sound pulses transmitted from one transducer to another. Depending on the mounting configuration, the signal may cross the pipe once, twice or four times. To measure flow the transit time is compared between ultrasonic signals travelling upstream and downstream.

TTFM 6.1 Standard Features Include:

  • One pair of SE16B ultrasonic transducers - clamp-on for 2” to 48” (50 mm to 1200 mm) pipes
  • Optional: one pair of SE16A ultrasonic transducers - clamp-on 0.5" to 4" (13 mm to 100 mm) pipes
  • Sensor cables - pair 25 ft / 7.6 m triaxial with BNC connectors
  • Flow rate range: ± 0.07 to 40 ft/sec (± 0.02 to 12 m/sec)
  • Installation - stainless steel transducer mounting brackets and clamps, alignment bar and silicone coupling compound kit
  • Enclosure - watertight, NEMA4X (IP66) polyester and polycarbonate
  • Display - white, backlit matrix
  • Totalizer - 14 digits
  • Programming - built-in 5-button keypad
  • Output - isolated 4-20mA (1000 ohm)
  • 2 Control relays - 5 amp, SPDT - programmable for flow proportional pulse output, and/or flow alarm
  • Power input - 100-240VAC 50/60Hz, 10VA maximum (Optional: 9-36VDC, 10 Watts maximum)
  • Data Logger – 128MB storage capacity, 26 million data points, formattable as .csv or .lg2 for Greyline Logger Software
  • Electrical surge protection and RFI filters - AC, sensor, 4-20mA
  • Plug-and-play options including MODBUS RTU output and extra control relays

Contact Greyline Instruments for specific recommendations in your application.

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Greyline Instruments Inc. Canada
16456 Sixsmith Drive, Long Sault, Ont. K0C 1P0
Tel: 613-938-8956 • Toll Free: 855-300-9151
Fax: 613-938-4857 • E-mail:

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Greyline Instruments Inc. United States
11451 Belcher Road South, Largo, FL 33773
Tel: 315-788-9500 • Toll Free: 888-473-9546
Fax: 315-764-0419 • E-mail:

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