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 - Discontinued Wall Mount Ultrasonic Flowmeter

FDT21W Series

Ultrasonic flow meter | Wall mount | FDT21W Series

Ultrasonic flow meter | Wall mount

  • Discontinued. See FDT-25W as a direct replacement.


See FDT-25W as a direct replacement.

FDT-21W ultrasonic flowmeter is designed to measure the fluid velocity of liquid in a full/closed pipe. It is a measurement system which is both easy to install and use.

The FDT-21W operates by measuring the transit time (or time of flight) of an ultrasonic pulse transmitted between two sensors clamped onto the outside of the pipe. These electro-acoustic transducers receive and emit brief ultrasonic pulses through the liquid of the pipe. The transit time of the ultrasonic pulses is proportional to the flow rate of the liquid.

Transducers are vertically placed at both sides of the measured pipe and fastened by means of a clamp. This external mounting means the transducers do not come into contact with the fluid being measured and the line does not have to be broken or drained for installation. The display will quickly show the flow velocity. The FDT-21W can be used for metallic, plastic and rubber lines.

Accuracy: ±1% of reading >(0.2 m/s) 0.6 ft/s
Repeatability: 0.2%
Linearity: 0.5%
Response Time: 0 to 999 seconds (user configured)
Velocity: (±0.01 to 30 m/s) ±0.03 to 105 ft/s bi-directional
Temperature Range: 0 to 160°C (32 to 320°F)
Pipe Size: DN 20 to 100 mm (0.75 to 4") standard [up to DN 6000 mm (236") with optional transducers]
Transducer Frequency: 1 MHz
Rate Units (User Configured): Meter, feet, cubic meter, cubic feet, USA gallon, oil barrel, USA liquid barrel, imperial liquid barrel, million USA gallons
Totalizer: 7-digit totals for positive, negative and net flow
Liquid Types: Most liquids including clean water, sea water, waste water, chemical liquids, oil, crude oil, alcohol, beer, and more
Suspension Concentration: ≤20,000 ppm (may contain very small amounts of air bubbles)
Pipe Material: All metals, most plastics and fibreglass
Security: Programmable lock-out code
Display: 2 x 16 english letters
Power: 85 to 264 Vac
Communications: RS485 (baud rate from 75 to 115,200 bps)
Transducer Cable Length: 5 m
Data Logger: Built-in, stores over 2000 lines of data
Totalizer/Calibration: 7-digit press-to-go for calibration
Housing: ABS plastic with aluminium alloy protective carrying case
Case: NEMA 4 (IP65)
Dimensions: 29 H x 20 W x 9 cm D
Weight: 514 g
Place Order(Specify Model Number)
Part Number/ Desc.
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Availability: In Stock
Wall mount transit-time ultrasonic flowmeter (Includes S2H transducer)
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Availability: 1 week
Replacement small pipe transducer (20 - 100 mm dia)
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Availability: 1 week
Medium pipe transducer (50 - 700 mm dia)
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Availability: 1 week
Large pipe transducer (300 mm - 6 m dia)
Pipe Clamps
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Availability: 1 week
(Replacement) Transducer pipe clamp set for up to DN100 (4")
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Availability: 1 week
Transducer pipe clamp set for up to DN200 (8")
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Availability: 8 weeks
Transducer pipe clamp set for up to DN300 (12")
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Availability: 7 weeks
Transducer pipe clamp set for up to DN400 (16")
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Availability: 1 week
Transducer pipe clamp set for up to DN500 (20")
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Availability: 1 week
Transducer pipe clamp set for up to DN600 (24")
All amounts shown in EUR, GBP, or USD
Note: Comes complete with standard size high temperature transducers (S2H), M2 memory storage card, transducer cable (2 @ 5 metres), transducer clamps (DN100), allen (hex) wrench, 10 terminal spade lugs, shrink tubing and operator's manual.
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