Greyline Instruments DFM 6.1 Doppler Flow Meter
Starting at $2,495.00

Some models in stock. View available part numbers.

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  • Flow rate: ±0.1 to 40 ft/sec (±0.03 to 12.2 m/sec)
  • Pipe size: 1/2 to 180in (12.7mm to 4.5m)
  • Accuracy ±2%:
    • Requires solids or bubbles of at least 100 microns
    • 75ppm concentration
  • ±0.1%, Linearity ±0.5% of full scale repeatability
  • Large, backlit LCD display
  • 16-Digit totalizer
  • Reverse flow measurement
  • Isolated 4-20mA (1000 ohm load max)
  • 2 programmable control relays
  • 26 Million Point Data Logger

The Greyline Instruments DFM 6.1 Doppler Flow Meter is a simple, non-contact meter designed for applications that would defeat regular contacting flow meters. Because the sensor is mounted on the outside of the pipe, it is unaffected by abrasives or harsh chemicals making it ideal for wastewater, slurries, sludge, chemicals, viscous liquids and abrasives. There is no obstruction to flow and no pressure drop. The DFM 6.1 is recommended for full pipes and any fluid that contains solids or bubbles.

The DFM 6.1 clamp-on sensor is mounted on the outside of any pipe 1/2in / 12.7mm diameter or larger. To measure velocity an acoustic signal is reflected back to the sensor from moving particles or gas bubbles suspended in the fluid. Flow is calculated based on configured pipe ID.

The DFM 6.1 Doppler Flow Meter includes an ultrasonic sensor, an easy to use 5-key calibration system, a large digital flow rate display with totalizer, isolated 4-20mA output, 26 million point data logger, and two programmable control relays. The sensor is classified as non-incendive and an intrinsically safe sensor is optional.

Greyline Instruments CHS Spare Electronics Set
Spare set electronics with mounting chassis (standard features)
Part Number Price Available
DFM 6.1-A-1-A-1-A-1-A-1-A
Show Configuration
Base Price
Power Input
Standard: 100 to 240VAC 50/60Hz
Enclosure & Electrical Protection
Standard: NEMA4X (IP66) polycarbonate
Enclosure Temperature Rating
Standard: -5 to 140°F (-20 to 60°C)
Intrinsic Safety
Standard, SE4 sensor rated non-incendive for Div 2, Groups A,B,C,D
Cable Length
Standard: 25ft (7.6m) shielded coaxial pair
Standard: none
Control Relay
Standard: 2 relays, rated 5 amp SPDT, programmable
$2,495.00 4

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