Clamp-on Ultrasonic Flow Meters

Clamp-on ultrasonic flow meters are used to measure flow rates and/or totalised flow of fluids and liquids in pipework. This type of meter has an interface for setting various parameters of the application. It will give a required sensor spacing and then a pair of sensors (ultrasonic transducers) are clamped onto the outside of the pipe. The meter will send signals upstream and downstream between the sensors to determine and indicate the rate of flow.

Ultrasonic flow meters are generally straightforward to operate and maintain, and can be used to measure the flow of most types of liquids and fluids. Ultrasonic flow meters are versatile and adaptable, and are suitable for use in a wide range of applications. At Zedflo, we stock both portable and fixed installation meters, and these can be used without the need to cut into the pipe.

Ultrasonic flow meter calibration services: pFlow ultrasonic flowmeter displaying a reading of 2146.30. Pipes and additional calibration equipment visible.

Comparison table

Model FT221 P117 P118i UW-30P D116 D118 UFW-100
Image FT221 FlowT Ultrasonic Flow Meter, transmitter and sensors Portable flow meter measuring flow rate in a pipe. The ultrasonic device displays a reading of 20.135. Cables connect the meter to sensors on the pipe. P118i Portable Transit Time Flow Meter: Flowmeter attached to a pipe, displaying flow rate. The device has a screen and keypad for operation. UW-30P ultrasonic flow meter on pipe D116 Wall Mount Transit Time Water Flow Meter. Close-up of a pFlow D116 transit time flow meter with a digital display and keypad for settings. D118 ultrasonic flow meter UFW-100 Fixed Transit Time Flow Meter. Close-up of the flow meter's electronic control box and sensors attached to a pipe, showing its installation.
Flow velocity range 0.03 to 12 m/s 0.01 to 6 m/s 0.01 to 12 m/s -30 to +30 m/s bidirectional 0.01 to 5 m/s 0.01 to 12 m/s -30 to +30 m/s bidirectional
Portable or fixed Portable Portable Portable Portable Fixed (wall mount type) Fixed (wall mount type) Fixed (wall mount type)
Waterproof? IP54 (splashes only) IP54 (splashes only) IP54 (splashes only) Yes, IP65 Yes, IP65 Yes, IP65 Yes, IP65
Power source Internal battery. ~16 hours run time Internal battery. ~6 to 10 hours run time Internal battery. ~10 hours run time Internal battery. ~12 hours run time Needs 10-36VDC power (not included) Needs 90-245VAC or 10-36VDC power (not included) Needs 110 / 230VAC or 24VDC optional
Pipe size range DN40 – 1200 (with standard transducers, special order sensors for as low as DN15) DN25 – 1200 (one set of transducers) [though it best suits 40mm+] DN25 – 6000 (one set of transducers covers full range) [though it best suits 40mm+] DN13 – 5000 (various sets of transducers) DN25 – 1200 (one set of transducers) [though it best suits 40mm+] DN25 – 5000 (one set of transducers) [though it best suits 40mm+]  DN25 – 600 (one set of transducers)
Transducer mounting method Magnetic mounting frames, chains included. We find the magnets to be pretty weak but with chains it mounts nicely and no tools needed Magnetic mounting frames or mounted to plasic pipes with straps, screwdriver required Magnetic mounting frames or mounted to plasic pipes with straps, basic tools required An excellent mounting frame attached w/ chains, no tools needed Mounted with straps only, screwdriver required Mounted with straps only, screwdriver required Mounting frames attached  by straps, screwdriver required
Accuracy spec  2% 1% 0.50%  1% to 2%  1%  0.5%  1% to 2.5%
Country of Manufacture China China China Japan China China Japan
Data logging? Yes Yes Yes Yes No Yes Yes
Stock/Lead time Typically stocked, nil stock lead time is ~4 weeks Typically stocked, nil stock lead time is ~4 weeks Special order, ~4 week lead time Special order, ~9 week lead time Typically stocked, nil stock lead time is ~4 weeks Typically stocked, nil stock lead time is ~4 weeks Special order, ~9 week lead time
*Price, From: 2950 +GST $3450 +GST $7750 +GST $13000 +GST (POA) $1900 +GST $3995 +GST POA
Comments This is a new model we introduced as a budget option, some key features include: suitable to measure higher valocities (12m/s), good versatile sensors and frames, and quite good battery life. The interface is less user friendly or easy to operate compared with the P117, and the carry case is not as nice. But once you get used to using it measurements are generally versatile and it is priced very economically. Another advantage is this model can be special ordered with small size transducers/sensors, meaning use on very small pipes as low as DN15 can be achieved achieved. P117-HD is an evolution of the P117, it has a nicer display with clear HD text and cleartype fonts, and upgraded internal hardware. It’s got great magnetic mounting frames making use on metal pipes quick and easy, but a bit annoying to mount on plastic pipes with included straps, or for quick mounting cable ties work well. The user interface, ease of operation, quick response of scrolling through menus, clear and bright screen in a small handheld size and quality transport case make this a fair bit nicer to operate over say the FT221, however a key downside is that it has a max measurement velocity of only 6 m/s (comparatively quite low) This has some key advantages over the P117-HD including: Better internal electronics and technology which offer better response, higher accuracy, improved signal strength with a stronger wide band output frequency, so it can handle perhaps some situations where the say a cheaper model may struggle, it can work with a larger pipe size range (upto DN6000), suitable to measure higher velocities (12m/s), colour screen The most expensive model in our range but it’s a high quality unit from the Tokyo Keiki with some very nice features and functions, it’s almost certainly the pick of the bunch but is priced as such, it has a very wide bidirectional suitable flow range of +/- 30m/s, with various different sensor kits available to fine tune suitability for specific applications. It’s excels with very small pipes and very large pipes. This model you can choose both fluid and material as ‘other’ and manually input the sound speed, where the p117-HD model has some limitations in that regard. It’s also IP65, the only portable model to achieve this in our range Original P116 was discontinued and this model P116-HD replaced it, it unfortunately was a measurement spec downgrade in the HD model, key difference being that you can only select the pipe material as very few materials, it’s not compatile with any liners, and it can only be used with water as the liquid with no ability to change the liquid to anything else. Be aware it can only manage a reletively low flow velocity of 5m/s and does not datalog. It is however economically priced so often purchased many units at once for example to use in a large building/site to monitor many flow lines and send data to a BMS. P118-HD replaced old P118 and this is actually a pretty nice technology upgrade with no measurement spec downgrade like other models of this brand receieved. The HD model introduced an improved colour display and maintains it’s good tech spec. This model has a very good accuracy spec, quite a high flow velocity range (12m/s) a wide pipe size range, and lots of program customisation – it has lots of pre-programmed liquids and pipe materials, and ability to set them as ‘other’ and enter a custom sound speed. The most expensive wall mount model we offer but it is a high quality Japanese made unit and it does have a large flow velocity range (30 m/s) Note this has a 4 button interface on the unit itself, while you can confiugre it with these buttons, the best way to setup the unit is with included PC software. Just plug in the meter by USB to a laptop and the software has an installation ‘EZ wizard’ which is very easy to follow and get it running with a large clear interface. Then once running likely all you want to see on the unit itself is flow rate and totaliser anyway so it works well for that. This model has very fast resonse and time to stable readings compared with other models.

* note that prices shown here in this table may not be accurate or current, its for indicative purposes at the time of writing, please check on the product page for current price or enquire