『Isco Laser Flow Meter Review: Non-Contact Laser Doppler Velocity Technology for Unstable Sewer Channels』Related information(clamp on meter|electromagnetic meter|venturi meterrotameter|orifice meter|ultrasonic flow meter|mass flow meter|coriolis mass flow meter|coriolis flow meter|magnetic flow meter|magmeter flow meter|magflow flow meter|mag meter flow meter|electromagnetic flow meter|vortex flow meter|turbine flow meter|thermal mass flow meter|thermal flow meter|rotameter flow meter)
Isco Laser Flow Meter Review: Non-Contact Laser Doppler Velocity Technology for Unstable Sewer Channels
Quick Answer: The Isco Laser Flow Meter is a non-contact open channel flow meter for wastewater channels with unstable flow profiles. It uses laser Doppler velocity sensing and an ultrasonic level sensor to calculate flow from surface velocity and water level. This method works well in sewer channels that carry rags, solids, and grit. For full pipe or high accuracy custody transfer, another meter type may perform better.
What the Isco Laser Flow Meter Does
Teledyne Isco builds the LaserFlow meter for open channel wastewater applications. The meter mounts above the flow stream. There is no contact with the water. This matters in sewer lines that carry rags, solids, fats, and grit. Sensors stay clean and maintenance stays low.
The unit fires a laser beam at the flow surface. The beam reflects off particles and bubbles moving with the water. A Doppler shift gives surface velocity. At the same time, an ultrasonic level sensor measures the water level. The onboard controller uses channel geometry to calculate flow rate in m3/h or MGD.
The operator enters the channel shape into the controller. Common shapes include rectangular channels, round pipes, and trapezoidal channels. The meter does not need a flume or weir. That saves civil work. For many plants, this is the biggest reason to choose a non-contact laser meter.
Where Laser Doppler Helps in Sewer Channels
Many open channel flow meters depend on a primary device such as a Parshall flume or a weir. These devices need civil work and can block solids. A laser velocity meter does not need a flume. It can be installed above a concrete channel or a rectangular sewer. That saves civil cost. This is a real benefit for municipal wastewater plants in Indonesia, Vietnam, and the Philippines where budget and civil work are constraints.
Unstable sewer channels often have fast surface velocity and slow bottom velocity. The flow profile changes from hour to hour. The Isco meter uses an internal velocity profiling routine to estimate mean velocity from surface velocity. Field accuracy depends on the velocity distribution. In typical municipal channels, many plants report deviation of 3 percent to 6 percent against a reference flow meter. Under very turbulent or surging conditions, the deviation can go higher.
We have seen this on customer sites in Southeast Asia. A plant with a short inlet channel had unstable readings during morning peak flow. The surface velocity spiked while the level stayed low. The meter needed a longer straight run to stabilize the readings. Most engineers skip this part. The site layout matters more than the meter itself.
Key Specifications and Practical Limits
Typical LaserFlow velocity range is 0.2 to 6 m/s. Level measurement range varies by sensor model, often up to 3 m or more. Output options include 4-20 mA, Modbus, and optional HART. Some versions have ATEX Zone 1 certification for hazardous areas, but most wastewater plants do not need that.
Here is the thing. Foam and mist cause the biggest field failures with this meter. Heavy foam can scatter the laser beam before it reads the water surface. That produces bad velocity data. Grease and floating deb
Another point is the installation site. The meter works best over straight channel runs. The manufacturer recommends a straight section of at least 10 times the channel width upstream. In cramped lift station outlets, this distance is not always possible.
Because the meter calculates flow from surface velocity, a uniform velocity profile matters. In deep channels over 2 m, the surface velocity may not represent the average velocity. A field calibration against a reference meter helps. In some plants, the reading is corrected by a factor from 0.85 to 0.95. That factor changes with water level and flow conditions.
Silver Instruments Alternative for Wastewater Channels
Silver Instruments supplies a range of flow meters for water and wastewater plants. For open channels that need non-contact measurement, we can provide an ultrasonic open channel flow meter with a Parshall flume or a velocity area sensor. For full pipe applications, our electromagnetic flow meters cover DN10 to DN2000 with 4-20 mA HART and Modbus outputs. We also stock pressure transmitters for level and pump control.
We have supplied flow meters to water treatment plants in the Philippines, a paint manufacturer in Vietnam, and food plants in Australia. One recent customer in West Java used our electromagnetic flow meter with PTFE liner for wastewater sludge. The meter measured flow of 15 m3/h at 2 bar pressure and 30 degrees Celsius. The signal is stable even with solid content up to 3 percent.
If you are comparing the Isco LaserFlow with other open channel meters, tell us your channel width, water level range, flow range, and solids content. We can suggest a suitable meter and a price.
Contact Silver Automation Instruments at Tel: +86-25-68650347 or Whatsapp: +86-25-52155837. WeChat: +86 15365082610. Our team can answer technical questions for Southeast Asia, Oceania, Latin America, and the Middle East.
FAQ: Laser Flow Meter Open Channel Measurement
Does the Isco Laser Flow Meter work in raw sewage? Yes. The non-contact design handles raw sewage with solids. But heavy foam and floating grease reduce accuracy.
What is the typical accuracy of a laser Doppler velocity meter in a sewer channel? Under stable flow and a straight channel, many sites report 3 percent to 6 percent deviation from reference. Under surging or foaming conditions, accuracy drops.
Do I need a Parshall flume with the Isco LaserFlow? No. A flume is not required. The meter reads surface velocity and level. You still need a known channel shape for flow conversion.
Can I use this meter in a partially filled pipe? Yes. The laser velocity method works in open channels and partially filled pipes. The level sensor tracks water height. The controller calculates area and flow.
What alternative is available for full pipe wastewater from Silver Instruments? For full pipe applications, we recommend an electromagnetic flow meter with 4-20 mA HART and rubber or PTFE liner. Send us pipe size DN, flow range in m3/h, pressure in bar, and temperature in degrees Celsius.
Hot Blog
Related AD
