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Ultrasonic Flow Meter DISCONTINUED Replaced by FDT-25

Item# FDT-21

Ultrasonic Flow Meter DISCONTINUED Replaced by FDT-25 FDT-21 FDT-21
  • Accuracy 1%
  • Repeatability 0.2%
  • Positive, Negative and Net Totalizer
  • 4-Line LCD Display
  • Clamp On Transducers
  • RS232 Output

  • Accuracy Value ±1% of reading >(0.2m/s) 0.6 ft/s
  • Batteries Included Yes
  • Battery Type Ni-H
  • Data Logging Built-in
  • Enclosure Material ABS plastic with aluminum alloy protective carrying case
  • Linearity 0.5%
  • Measurement Type Flow
  • Measurement Units Meter
  • Media Type Most liquids including clean water
  • Number of Batteries 3
  • Number of Display Digits 7
  • Repeatability 0.2%
  • Power Source Battery
  • Velocity (±0.01 to 30 m/s) ±0.03 to 105 ft/s bi-directional
  • Tranducer Frequency 1 MHz
meter is designed to measure the fluid velocity of liquid in a full/closed pipe. It is a handheld measurement system which is both easy to install and use. The FDT-21 operates according to the difference in the transit time of flight measured, and determines the flow velocity by measuring the travel time of a pulse from one transducer to the next.

Flow in the same direction takes less time to travel to the second transducer than does flow in the opposite direction. Electroacoustic transducers receive and emit brief ultrasonic pulses through the liquid of the pipe. Transducers are vertically placed at both sides of the measured pipe. Sensors are placed on the pipe and fastened by means of a clamp. The display will quickly show the flow velocity. The FDT-21 can be used for metallic, plastic and rubber tubes.

±1% of reading >(0.2m/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:
    Standard: 0 to 70°C (32 to 158°F)
    With High Temp Transducers: 0 to 160°C (32 to 320°F)
Pipe Size: DN 19 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, liter, 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 fiberglass
Security: Programmable lock-out code
Display: 4 x 16 english letters
Communications: RS232C (baud rate from 75 to 115,200 bps)
Transducer Cable Length: 5 m (15')
Power: 3 "AAA" Ni-H built-in batteries (included) with 90 to 230 Vac charger, fully charged lasts over 12 hrs.
Data Logger: Built-in, stores over 2000 lines of data
Totalizer/Calibration: 7-digit press-to-go for calibration
Housing: ABS plastic with aluminum alloy protective carrying case
Case: NEMA-4 (IP65)
Dimensions: 100 H x 66 W x 20 mm D (3.9 x 2.6 x 0.8")
Weight: 514 g (1.2 lb)
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Rated 4 out of 5 by from FDT-21 I have been using this easy to use product for several years for a specific "as-found" and "as-left" Hydrogen Seal Oil flows before and after my nuclear plant's refueling outages.
Date published: 2018-02-19
Rated 5 out of 5 by from Worked right out of box! Very easy to setup and connect, worked right out of the box with included cables!
Date published: 2017-08-12
Rated 4 out of 5 by from Great Features i recently bought this product and i am happy to have it
Date published: 2019-04-03
Rated 1 out of 5 by from Junk Cables Unit works, but cables are junk and not in stock !!
Date published: 2017-11-01
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This item is no longer available to purchase. For questions contact sales
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