Flow Meters › Ultrasonic Flow Meters › Strap-On Ultrasonic Flow Meter
Strap-On Ultrasonic Flow Meter (X3)
An all-in-one clamp-on meter for small pipes. The transducers and the display are built into one block that straps onto the outside of the line with a magnetic bracket, factory-set for the pipe size, so it reads flow in minutes with nothing cut and nothing wetted. Built for clean liquids on small machine and process lines.
- Principle: transit-time, integrated clamp-on
- Pipe size: Φ9.53 to Φ110 (DN6 to DN100)
- Velocity: 0.1 to 5 m/s; accuracy ±2%
- Display: 1.3 in OLED, four-key; 7-digit totalizer
- Output: 4-20 mA, RS-485; 24 VDC; IP54/IP65
Overview
A standard clamp-on ultrasonic meter is a wall-mounted convertor wired to a pair of separate transducers: powerful and configurable, but more than a small machine or a single dosing line needs. The X3 collapses all of that into one block. The sensor and the OLED display sit in a single aluminum case that straps onto the outside of the pipe with a magnetic bracket, and it leaves the factory already set for the pipe diameter, so there is no field configuration. Clamp it on, give it 24 V, and it reads.
It is built for small lines, Φ9.53 to Φ110 (DN6 to DN100), on stainless, carbon steel, copper, or plastic pipe, and reads from 0.1 to 5 m/s at ±2%. With a 4-20 mA output and Modbus RS-485 it drops straight into a machine or a panel. For larger pipes, or where you need a separate remote display and full configuration, use the clamp-on ultrasonic flow meter with its wall convertor instead.
Features
The whole point is a clamp-on meter small and simple enough to build into a machine.
All-in-one block
Sensor and display in a single case that straps on with a bracket; no separate convertor to wire.
Factory-set, magnetic mount
Each unit ships set for its pipe size; strong magnets hold it for a fast two-screw install.
Small-bore range
Twelve sizes from Φ9.53 to Φ110 (DN6 to DN100), where most clamp-on meters do not reach.
OLED and totalizer
A 1.3 in OLED, rotatable 180 degrees, shows rate, velocity, and net, daily, and monthly totals.
4-20 mA, RS-485, relay
Analog output and Modbus RS-485, with an optional OCT alarm and relay, for machine integration.
Non-invasive
Nothing enters the pipe, so there is no pressure drop and no contact with the liquid.
Working principle
Like any transit-time meter, the X3 times an ultrasonic pulse across the pipe in both directions. The pulse travelling with the flow arrives a little sooner than the one travelling against it, and the difference between the two travel times is proportional to the velocity; the meter multiplies by the bore to give flow, timed by a chip accurate to better than 10 picoseconds. What is different is the packaging. The transducers are built into the underside of the case, so when the block is strapped to the pipe they are already aligned, and because each unit is set at the factory for one pipe size there is no wall-thickness or spacing to enter. The trade for that simplicity is range: it is built for a clean single liquid in small pipes, not for the wide size span of a separate-transducer convertor.
Technical specifications
| Parameter | Specification |
|---|---|
| Measurement principle | Transit-time ultrasonic, integrated clamp-on |
| Pipe range | OD Φ9.53 to Φ110 (DN6 to DN100) |
| Velocity range | 0.1 to 5 m/s |
| Accuracy | ±2% at 0.5 to 5 m/s; repeatability 0.8% |
| Response | 500 ms |
| Liquid | Single clean liquid, no bubbles; inclusions under 4%; viscosity under 300 cSt; pressure to 0.3 MPa |
| Pipe material | Stainless steel, carbon steel, copper, or plastic (PVC, CPVC, PVDF, PPR, PPH, HDPE) |
| Display | 1.3 in 128 x 64 OLED, rotatable 180 degrees; 7-digit; four touch keys |
| Units and totals | m³/h, LPM, GPM, LPH; net, single, and day/month/year totalizer |
| Data storage | 10 years, 64 months, 64 days; CR1220 calendar battery |
| Outputs | 4-20 mA (max 600 ohm); RS-485 Modbus RTU; OCT alarm and relay 30 VDC 1 A optional |
| Power supply | 24 VDC, 3 W (220 VAC via external converter) |
| Temperature | Medium and ambient -10 to 50 C (high-temperature version to 120 C) |
| Case and protection | Aluminum alloy; IP54/IP65 |
| Cable | 2 m standard, extendable to 20 m |
Representative specifications. Values typical; confirm per datasheet for your pipe size.
Ordering example. X3-Φ25 strap-on flow meter for a Φ25 (DN20) stainless line, 4-20 mA and RS-485, 24 VDC, with magnetic bracket.
Pipe sizes
The meter is ordered to the pipe outside diameter; each size ships with the matching bracket and factory setup. Twelve sizes cover DN6 to DN100.
| Model | Outside diameter | Nominal bore | NPS |
|---|---|---|---|
| X3-Φ9.53 | Φ9.53 mm | DN6 | 1/8″ |
| X3-Φ12.7 | Φ12.7 mm | DN8 | 1/4″ |
| X3-Φ15 | Φ15 mm | DN10 | 3/8″ |
| X3-Φ20 | Φ20 mm | DN15 | 1/2″ |
| X3-Φ25 | Φ25 mm | DN20 | 3/4″ |
| X3-Φ32 | Φ32 mm | DN25 | 1″ |
| X3-Φ40 | Φ40 mm | DN32 | 1-1/4″ |
| X3-Φ50 | Φ50 mm | DN40 | 1-1/2″ |
| X3-Φ63 | Φ63 mm | DN50 | 2″ |
| X3-Φ75 | Φ75 mm | DN65 | 2-1/2″ |
| X3-Φ90 | Φ90 mm | DN80 | 3″ |
| X3-Φ110 | Φ110 mm | DN100 | 4″ |
Versions
The compact, all-in-one unit on this page is the standard. For pipes or service the compact build does not cover, the same meter comes in a split form, with the transducer on the pipe and the display mounted remotely:
- Compact (integrated). Sensor and display in one strapped-on block, medium -10 to 50 C. The default for clean liquid on a small accessible pipe.
- Split (separate). A remote transducer with the display mounted elsewhere, for a pipe that is hard to read at.
- Split high-temperature. A separate high-temperature transducer for media up to 120 C.
- Split anti-corrosion and PP. Corrosion-resistant transducer and housing materials for aggressive chemical service.
Tell us the pipe, the liquid, and the temperature and we set the build.
Applications
The X3 is made for clean liquids on small lines, where a clamp-on reading has to be compact and built in:
- Semiconductor ultrapure water and process chemicals
- Cleaning and washing equipment
- Beverage, food, and pharmaceutical process lines
- Fine-chemical dosing: acids, alkalis, solvents, alcohols
- Machine and OEM equipment needing an integrated flow readout
Application example
Cleaning-equipment builder, small process line. An equipment builder needed a flow reading on a small line inside a cleaning machine, with a 4-20 mA signal back to the controller, and no room or budget for a wall convertor and separate transducers. A strap-on unit sized for the pipe magnet-mounted onto the line and gave the readout and the analog signal from one compact block, set at the factory so the assembler had nothing to configure. It turned a flow measurement into a bolt-on part rather than an instrument install.
Related products
Clamp-On Ultrasonic Flow MeterWall convertor and transducers for larger pipes.
Portable Ultrasonic Flow MeterHandheld survey meter for spot checks.
Browse all ultrasonic flow meters →
FAQ
What is a strap-on flow meter?
It is a clamp-on ultrasonic flow meter built as one block, with the transducers and display together, that straps onto the outside of a pipe with a magnetic bracket. Nothing enters the pipe. The X3 is factory-set for the pipe size, so it reads as soon as it is clamped on and powered.
How is it different from a normal clamp-on meter?
A normal clamp-on meter is a separate wall convertor wired to two transducers, and you configure the pipe in the field. The X3 puts the sensor and display in one strapped-on case, set at the factory, for small pipes from Φ9.53 to Φ110 (DN6 to DN100). It is simpler and made to build into machines; the convertor meter covers larger pipes and full configuration.
What pipe sizes and liquids does it suit?
Outside diameters from Φ9.53 to Φ110 (DN6 to DN100) on stainless, carbon steel, copper, or plastic pipe, with a single clean liquid, no bubbles, inclusions under 4%. For dirty or solids-bearing liquid, a Doppler meter is the right tool.
What temperature can it handle?
The standard compact unit handles medium and ambient from -10 to 50 C. For hotter media, a split high-temperature version takes the liquid up to 120 C, and anti-corrosion and PP builds are available for aggressive chemicals.
Can it output to a PLC?
Yes. It gives a 4-20 mA analog signal and Modbus over RS-485, with an optional OCT alarm and relay, so it drops into a machine controller or a panel directly.
Request a quote
Send us the pipe outside diameter and material, the liquid and its temperature, and the output you need. We supply the X3 set for that pipe size with its bracket, in the compact or a split build.