Ultrasonic flow meters and level monitors Greyline Instruments

Industrial flow measurement manufacturer Greyline Instruments: clamp-on Doppler flow meters, transit-time liquid meters, area-velocity open channel monitors, and controllers.

Clamp-on ultrasonic Doppler flow meters series DFM 6.1

Clamp-on ultrasonic flow meters Greyline series DFM 6.1 deliver continuous flow velocity monitoring for aerated liquids, slurries, and raw wastewater. The external transducer attaches to pipe walls from 12 to 4500 mm outer diameter without interrupting active operations.

Acoustic clamp-on transducer PZ15 suitable for pipe sizes from 12 to 4500 mm outer diameter
Analog 4-20 milliamp loop output alongside programmable relays and digital Modbus interface
Built-in data logger storing up to three hundred thousand points with USB export capability
Rugged weatherproof enclosure rated NEMA 4X for severe municipal and industrial installations

Transit-time ultrasonic clamp-on flow meters series TTFM 6.1

Transit-time ultrasonic flow meters Greyline series TTFM 6.1 measure volumetric liquid flow in fully flooded pipes using ultrasonic differential propagation velocity. Matched clamp-on acoustic transducers mount externally without cutting lines or causing system pressure drop.

Matched pairs of clamp-on transducers engineered for pipes from 50 to 1200 mm diameter
Automatic ultrasonic signal optimization adapts to varying fluid acoustic properties
Isolated 4-20 milliamp output and programmable setpoint relays for process telemetry
Convenient keypad configuration menu allowing quick pipe wall and fluid data entry

Area-velocity open channel flow meters series AVFM 6.1

Area-velocity flow meters Greyline series AVFM 6.1 monitor open channels, storm sewers, and gravity conduits without requiring primary flumes. A submersible stainless sensor continuously tracks fluid level and velocity distribution to calculate totalized discharge rates.

Submerged sensor combines ultrasonic Doppler velocity and level measurement functions
Pre-programmed formulas for round, rectangular, trapezoidal, and custom canal profiles
Computational velocity profiling engine computes discharge across variable wet depth
Hydrodynamic sensor design sheds debris and prevents sediment fouling in sewer mains

Portable ultrasonic Doppler flow meters series PDFM 5.1 and 6.1

Portable Doppler flow meters Greyline series PDFM 5.1 and PDFM 6.1 are designed for field balancing, verification audits, and temporary pipeline monitoring. The system includes an internal rechargeable battery, handheld sensor, and heavy-duty IP67 transport enclosure.

Internal rechargeable lithium power pack delivers up to 18 hours continuous operation
Ergonomic handheld transducer kit complete with mounting straps and acoustic couplant
Built-in logging memory for three hundred thousand readings with direct USB file dump
Graphic backlit display reveals real-time flow rate, cumulative volume, and waveform

Non-contacting ultrasonic level and pump controllers series SLT 5.0

Ultrasonic level controllers Greyline series SLT 5.0 and PSL 5.0 provide non-contacting level measurement within storage tanks, sumps, and municipal pump wet wells. Advanced DATEM digital echo processing rejects false reflections from ladders, agitator blades, and pipes.

Non-contact ultrasonic sensing range spanning up to ten meters depth in closed sumps
Proprietary DATEM echo algorithm tracks true liquid level through turbulent echoes
Up to five programmable control relays for pump sequencing and high level alarms
Isolated 4-20 milliamp loop output communicating with plant supervisory controllers

Open channel flume flow meters series OCF 6.1 and transducers

Ultrasonic flume flow meters Greyline series OCF 6.1 compute flow rates through standard primary weirs and flumes. The hardware line includes Doppler sensors PZ15 and PZ34, transit-time pairs SE4, stainless mounting hardware PC4, and low-loss high-frequency sensor cables.

Pre-loaded discharge equations for Parshall flumes, Palmer-Bowlus, and V-notch weirs
Replacement acoustic sensors featuring corrosion-resistant polymer face construction
Stainless steel transducer mounting tracks PC4 ensuring stable alignment on pipelines
High-frequency low-noise sensor cables with braided shielding against electrical noise

Heritage of Greyline Instruments and integration into Pulsar Measurement

The engineering background of Greyline Instruments originated in 1986 in Long Sault, Ontario, Canada and Massena, New York, USA.

The enterprise concentrated on developing ultrasonic instrumentation to resolve demanding industrial challenges in non-contact flow monitoring of slurries, raw wastewater, and corrosive chemicals within pressurized piping systems.

Following strategic integration into the international TASI Measurement group, Greyline Instruments amalgamated engineering teams, technology portfolios, and manufacturing facilities with Pulsar into Pulsar Measurement.

Today the combined organization operates three advanced manufacturing facilities and engineering centers across the United Kingdom, Canada, and the United States.

Operational methodology and electronics of Doppler flow meters DFM 6.1

Clamp-on flow meters Greyline series DFM 6.1 operate on the physical principle of the acoustic Doppler effect.

An external acoustic transducer PZ15 mounts to the outer pipe wall using high-viscosity silicone couplant, transmitting continuous ultrasonic signals through the pipe material into the moving stream of liquid carrying suspended solids or aeration.

Echo reflections returning from particulate interfaces arrive at the receiving piezoelectric element with a frequency shift directly proportional to fluid velocity.

An integrated digital processor calculates instantaneous linear velocity, derives volumetric flow according to pipe internal diameter, and transmits an isolated 4-20 milliamp signal to plant supervisory systems.

Transit-time ultrasonic measurement technology for clean liquids in TTFM 6.1

For volumetric flow measurement of clean, non-aerated industrial fluids and potable water within full closed pipes, Greyline developed the transit-time TTFM 6.1 instrument family.

This methodology relies on differential propagation time measurements of ultrasonic pulses traveling diagonally across the moving fluid stream upstream and downstream.

A matched set of clamp-on transducers SE4 attaches to the exterior pipe surface along standard V-method or W-method acoustic paths.

High-speed electronic timers detect nanosecond propagation arrival deltas, providing repeatable volumetric flow computation without pipe penetration, shutdown downtime, or hydraulic pressure loss.

Area-velocity monitoring in unpressurized conduits and open channels AVFM 6.1

Measuring fluid discharge through partially filled pipes, culverts, and open channels presents demanding hydrological requirements due to shifting flow depth and velocity distribution profiles.

Greyline AVFM 6.1 flow meters deliver continuous monitoring using the area-velocity principle with a single submerged stainless sensor positioned on the invert.

The integrated echo sounding transducer continuously detects fluid depth to calculate cross-sectional wetted area from pre-programmed channel geometry formulas.

Concurrently, an ultrasonic Doppler velocity array measures average stream velocity across the vertical profile, calculating totalized volume without constructing flumes.

Portable instruments series PDFM for system auditing and pipeline verification

For field service engineers, municipal maintenance crews, and environmental auditors, portable Doppler flow meters Greyline series PDFM 5.1 and PDFM 6.1 provide a versatile mobile measurement tool.

The unit is housed in a compact weatherproof IP67 enclosure equipped with an internal rechargeable lithium battery providing up to eighteen hours of continuous autonomous operation.

The standard field kit includes a portable clamp-on transducer, flexible mounting chains, a bottle of acoustic coupling compound, and high-frequency connecting cable.

Internal memory stores up to 300 000 data logs with rapid USB export capability to generate comprehensive pump balancing and water network audit documentation.

Ultrasonic level controllers SLT 5.0 and DATEM echo processing technology

Non-contacting ultrasonic level controllers Greyline series SLT 5.0 and lift station controllers PSL 5.0 provide continuous monitoring of liquid levels and volume within process vessels, wet wells, and sumps.

A key technical capability of the instrument line is the proprietary DATEM digital echo processing algorithm (Digital Adaptive Tracking of Echo Movement).

The software engine continuously evaluates echo signal profiles within the wet well, adjusting threshold sensitivity curves to ignore false echoes returned by internal pipes, ladders, sidewall buildup, and agitator blades.

The controller incorporates five configurable power relays for alternating pump lead-lag cycles and automated scum line prevention.

Greyline Instruments and model names are trademarks of their respective owners and are used only to identify the equipment for which we source parts. SpareX is not an official dealer, distributor or representative of Greyline Instruments and is not affiliated with the trademark owner. Origin, documents and warranty are stated for each item in the quotation.