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  1. Flow Meters
  2. Ultrasonic Flow Meters

Greyline Instruments DFM 5.1 Doppler Flow Meter

Non-contact ultrasonic meter accurately displays, transmits, totalizes and controls flow from outside the pipe.

Greyline Instruments DFM 5.1 Doppler Flow Meter
Greyline Instruments DFM 5.1 Doppler Flow Meter
Retired products cannot be ordered
The Greyline Instruments DFM 6.1 Doppler Flow Meter is the recommended replacement

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Manufactured
  • By Pulsar Measurement, Trading Name of Greyline
Includes
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  • FREE Lifetime Tech Support
Product Manual Product Specs
Questions?
Call 1-800-884-4967 or email sales@instrumart.com. Open 8:00 am to 5:30 pm ET.
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Overview

Features

  • Flow Rate of ±0.1 to 40ft/sec in most applications
  • Any pipe ID from 1/2 to 180in
  • ±2% of scale accuracy
    • Requires solids or bubbles of at least 100 microns
    • 75ppm concentration
  • ±0.1%, Linearity ±0.5% of full scale repeatability
  • Large, backlit LCD display
  • 12-Digit totalizer
  • Reverse flow measurement
  • Isolated 4-20mA (1000 ohm)
  • 2 programmable control relays (upgradeable to 6)
  • Automatic sensitivity adjustment
  • Built-in 5-key calibrator
  • 2 million point data logger optional
    • USB output to flash memory

What's in the Box

  • SE4-A clamp-on, single head ultrasonic sensor
  • Shielded coaxial pair sensor cable
  • Silicone sensor compound kit
  • Sensor mounting clamp for 0.6 to 32in OD pipes
  • Installation and operation manual
  • NIST certificate

Description

The Greyline Instruments DFM 5.1 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 5.1 is recommended for full pipes and any fluid that contains solids or bubbles.

The Greyline DFM 5.1 works with PVC, carbon steel, stainless steel, cast iron, fiberglass, and lined pipes-- essentially any pipe material that conducts ultrasound. The non-intrusive, clamp-on ultrasonic sensor fits any pipe with an inside diameter from 1/2 to 180 inches. Installation is easy and doesn't require the system be shut down. No contact is made with the moving fluid and no pipe cutting or drilling is required. There is no fouling or scale build-up on the sensor.

The DFM 5.1 Doppler flow meter includes an isolated 4-20mA to transmit flow to remote displays, recorders or controllers. The two programmable relays (upgradeable to six) can be used for flow control, pump protection or flow proportionate pulse. Calibration is easy with the built-in 5-key calibrator. Display and totalize flow in your choice of engineering units (gallons, liters etc.). The standard sensor is rated non-incendive for Class I, Division 2 hazardous locations and the DFM 5.1 can be equipped with optional Intrinsic Safety Barriers for sensor installation in Class I, Division I hazardous locations. A built-in 2 million point Data Logger with USB output to Flash Drives is also available.

Documents

Spec Sheets

  • Greyline Instruments DFM 5.1 Doppler Flow Meter Datasheet PDF (172 KB)

Manuals

  • Greyline Instruments DFM 5.1 Doppler Flow Meter Manual PDF (1.2 MB)

Application Notes and White Papers

  • Sand Slurry Flow Monitoring PDF (240 KB)
  • Solution for Crude Oil Flow PDF (276 KB)

Other

  • Flow Application Information Form (268 KB)

Links

  • All possible part numbers

Accessories

Cables

Greyline Instruments DXC Sensor Cable
Greyline Instruments DXC Sensor Cable

RG174U shielded coaxial pair available in lengths up to 500 feet.

Starting at $130.00

Sensors/Probes

Greyline Instruments SE4-A Velocity Sensor
Greyline Instruments SE4-A Velocity Sensor

Clamp-on Doppler velocity sensor.

Some Models in Stock
Starting at $720.00

Accessories

Please consider these optional accessories.

Greyline Instruments JB2X Sensor Cable Junction Box
Greyline Instruments JB2X Sensor Cable Junction Box

NEMA4X/IP66 polycarbonate junction box for extending sensor cable lengths.

$62.00
Greyline Instruments CC Coupling Compound
Greyline Instruments CC Coupling Compound

Acoustic couplant is gel applied to the sensor face to ensure a complete acoustic pathway between the sensor and the pipe wall.

Starting at $55.00

Applications

This product can be used in the following applications:

  • Agricultural
  • Irrigation
  • Waste-water and Grey Water

Here's how some of our customers use this product...

Construction Site De-watering

The Background: Our customer is a large construction company currently working on a project in which groundwater has seeped into areas that have been excavated. The customer needs to monitor the amount of water they pump out of those areas.

The Problem: The water has a lot of suspended solids. Also, the customer does not need a long term solution, only something until the seepage is mitigated.

The Solution: Since power is available on site, the water contains sufficient suspended solids, and there was straight, full pipe available for installation, we recommended the Greyline Instruments DFM 5.1 doppler meter with onboard data-logger.

Measuring Spent Grain Flow

The Background: Our customer is a brewery that wants to monitor the flow of their spent grain discharge line.

The Problem: The spent grain line is water with high solid content making it a prime candidate for a Doppler style ultrasonic flow meter with clamp-on technology, though the customer is accustomed to measuring in mass units.

The Solution: We recommended the Greyline Instruments DFM 5.1 Doppler Flow Meter paired with a Define Instruments LD-PRC Panel Meter. Though the DFM 5.1 will only provide velocity measurement, by assuming a constant density of the spent grain, the 4 and 20mA scaling points of the LC-PRC can easily be manipulated to output a pound per minute mass flow rate.

In this particular application, the DFM 5.1 Doppler flow meter will output a 4-20mA signal that equates to 0-100 GPM (gallons per minute). The customer has provided a spent grain density of 7.753 lb/gal (pounds per gallon) so the 20mA programming in the LD-PRC is set to 775.3 lb/min (100 gal/min x 7.753 lb/gal = 775.3 lb/min).

Mining Slurry

The Background: Our customer is a mining company that needs to measure the amount of ore slurry transported through an 8-inch pipeline.

The Problem: The ore slurry contains about 75% solids which would quickly destroy any inline flow meter.

The Solution: We recommended the Greyline Instruments DFM 5.1 flow meter, a clamp-on ultrasonic flow meter that has no parts which obstruct the flow. The reliable Doppler technology has been proven to work very well even on extremely noisy, high solid content, lines.

Need Help? Call a Flow engineer at 1-800-884-4967

We're open 8:00 am to 5:30 pm ET

Patrick M. headshot Patrick M.
Applications Engineer
3 years at Instrumart
Martin K. headshot Martin K.
Applications Engineer
MaryKate R. headshot MaryKate R.
Applications Engineer
3 years at Instrumart
Lou P. headshot Lou P.
Senior Applications Engineer
28 years at Instrumart
Jason D. headshot Jason D.
Senior Applications Engineer
22 years at Instrumart
Mathias H. headshot Mathias H.
Senior Applications Engineer
15 years at Instrumart
Dan R. headshot Dan R.
Applications Engineer
3 years at Instrumart
Patrick M. headshot Patrick M.
Applications Engineer
3 years at Instrumart
Martin K. headshot Martin K.
Applications Engineer
MaryKate R. headshot MaryKate R.
Applications Engineer
3 years at Instrumart
Lou P. headshot Lou P.
Senior Applications Engineer
28 years at Instrumart
Jason D. headshot Jason D.
Senior Applications Engineer
22 years at Instrumart
Mathias H. headshot Mathias H.
Senior Applications Engineer
15 years at Instrumart
Dan R. headshot Dan R.
Applications Engineer
3 years at Instrumart
Patrick M. headshot Patrick M.
Applications Engineer
3 years at Instrumart

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Greyline Instruments DFM 5.1 Doppler Flow Meter
Greyline Instruments DFM 5.1 Doppler Flow Meter
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