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Greyline Instruments PDFM 5.1 Portable Doppler Flow Meter Get Quote



It's ideal for flow troubleshooting, balancing and checking performance of permanent flow meters. The new PDFM 5.1 is fast and easy to operate – you can mount the sensor on the outside of a pipe in less than a minute. Use the built-in keypad and calibration menu to set up the flowmeter for your application. The PDFM 5.1 works on any liquid containing bubbles or solids and is recommended for "difficult liquids" like wastewater, slurries, sludge, chemicals, viscous liquids and abrasives. Measures flow through most metal and plastic pipes including PVC, ductile iron, carbon steel and stainless steel.

The Greyline PDFM 5.1 is AC/DC powered with built-in NiMH batteries and external charger. With its 4-20mA output you can use the PDFM 5.1 as a spare transmitter in critical applications. For flow studies and troubleshooting use the built-in 300,000 point Data Logger. Retrieve data logs with 'Greyline Logger' software – included free with each PDFM 5.1. Connect the USB output directly to your PC or Laptop to download data logger files.

The PDFM 5.1 includes a non-intrusive Doppler ultrasonic sensor for pipes from 1/2" to 180" (12.5 mm to 4.5 m) diameter, a stainless steel sensor mounting bracket and clamps, coupling compound and AC charger with a rugged IP67 carry case. It operates up to 18 hours from internal batteries and recharges overnight.

Key Features

  • New signal processing for reliable accuracy
  • Sleep mode for extended data logging on battery power
  • Built-in 300,000 point datalogger and PC software
  • No calculations - no programming codes
  • Simple start-up and calibration
  • Battery powered for a full day's work
  • Quick, easy flow measurements from outside a pipe

Technical Specifications

Flow Rate Range: ± 1 ± 3 in most applications
Pipe Size: Ultrasonic Sensor mounts on any pipe from ½\" to 180\" ID (12.5 mm to 4.5 m)
Display: White, backlit matrix - displays flow rate, totalizer, operating mode and calibration menu
Power Input: Built-in battery NiMH for up to 18 hours continuous operation\nExternal with 24 input
Outputs: 4-20mA (500 ohm) when AC powered\nUSB for Data Log transfer by direct PC connection
Data Logger: P 30 programmable 0,000 data point capacity, time and date stamped or formatted flow reports including total, average, minimum, maximum and
PC Software: 'Greyline Logger' for Windows Vista or higher. Retrieves, displays and saves data log files
Electronics Operating Temperature: -10° to 140°F (-23° to 60°C)
Electronics Enclosure: Portable, ABC enclosure
Carry Case: Rated IP67 with protective molded foam insert
Accuracy: ±2% of reading or 0.1 ft/sec (0.03 m/sec). Requires solids or bubbles minimum size of 100 microns, minimum concentration 75 ppm. Repeatabili
Calibration: Built-in 5-key programming with user-friendly calibration menu. Password protected.
Language Selection: English, French, Spanish
Sensitivity: Adjustable, Damping: adjustable
Approvals: Charger is CE and UL approved. The PDFM 5.1 is not certified for use in hazardous rated locations