Starting at $2,195.00

Some models in stock. View available part numbers.

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  • Non-contacting ultrasonic sensor
  • Accurate and verifiable
  • ±0.25% of range accuracy
  • Built-in 2-million point data logger
  • USB outputs to Flash memory sticks
  • Isolated 4-20mA/0-5V output
  • 2 programmable control relays
  • Simple 5-key calibration with language selection
  • Password protected
  • On-screen flow reports
  • NEMA4X (IP 66) polycarbonate enclosure
    • Water & dust tight with shatterproof cover

What's in the Box

  • Level sensor
  • Coaxial sensor cable
  • Greyline Data Logger software for Windows
  • Installation and operation manual
  • NIST certificate

The Greyline Instruments OCF 5.0 open channel flow meter is designed to continuously monitor, display, totalize and data log flow through any flume or weir. Featuring an ultrasonic sensor that mounts above the flowing water, the OCF 5.0 will not obstruct the flow nor be prone to fouling.

The OCF 5.0 is easy to set up and operate. Use the built-in Keypad/menu system to select your flume or weir from the menu and to choose the measurement unit. Flow reports including minimum, maximum, average and total daily flow can be viewed directly on the backlit LCD display. The OCF 5.0 also includes a built-in, 2-million point data logger and flow reporting system. Connect a flash memory stick to the flowmeter's USB output to download log files and then view your data in graph and table formats with 'Greyline Logger' software.

The Greyline Instruments OCF 5.0 open channel flow meter has an isolated 4-20mA output which can transmit flow data to remote chart recorders or displays. The two control relays (upgradeable to six) are programmable for level/flow alarm, and flow proportionate pulse (for samplers, chlorinators or remote totalizers). An Intrinsic Safety Barrier is optional for sensor and cable installation in hazardous rated locations. The separate, watertight electronics/display enclosure is mounted at a convenient location within 500ft (150m) of the sensor.


Greyline Instruments XC Sensor Cable
RG62AU coaxial cable available in lengths up to 500 feet


Greyline Instruments PZ15-LP Level Sensor
Low profile, non-contacting ultrasonic level sensor ideal for confined spaces and small flumes
Greyline Instruments PZ15 Level Sensor
Non-contacting ultrasonic level sensor is small enough for very small flumes and powerful enough for really large applications.
Greyline Instruments PZ34 Level Sensor
Non-contact, PVC level sensor with 32 foot range with liquids
Greyline Instruments PZ32T Level Sensor
Non-contact, PVC and Teflon level sensor with 32 foot range with liquids
Greyline Instruments PZ32TE Level Sensor
Non-contact, Teflon level sensor with 32 foot range in liquids


Please consider these optional accessories.

Greyline Instruments JB2X Sensor Cable Junction Box
NEMA4X/IP66 polycarbonate junction box for extending sensor cable lengths
Greyline Instruments SMS Sensor Mounting Stand
Sensor Mounting Stand (for Open Channel applications) for the OCF 5.0 Open Channel Flow Monitor
Greyline Instruments SCR Enclosure Sunscreen
Enclosure Sunscreen (iridite aluminum)
Greyline Instruments PZS Sensor Sunscreen
Sensor Sunscreen (iridite aluminum)
Greyline Instruments SBMS Sensor Submergence Shield
Sensor Submergence Shield (PVC)
Greyline Instruments CHS Spare Electronics Set
Spare set electronics with mounting chassis (standard features)
Greyline Instruments SP1 Surge Protection
Lightning / surge protector in NEMA4 steel enclosure for use with the OCF 5.0 open channel flow monitor
Greyline Instruments MNL Additional Manuals
Additional Manuals (One supplied with each unit)
Greyline Instruments PM Enclosure Panel Mount Flange Assembly


This product can be used in the following applications:

Application Notes

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

Gravity Feed Flow Monitoring

The Background: Our customer is a commercial orchard that needs to monitor the amount of irrigation water being diverted from a nearby stream.

The Problem: The stream water is gravity fed into a pipe that transports the water to the orchard. Most flow meters require a completely full pipe to accurately measure the flow, something which is not possible in most gravity feed applications such as this.

The Solution: The customer was able to deploy a Greyline OCF 5.0 open channel flow monitor with a Parshall flume, enabling them to accurately monitor water usage. Compatible with a wide variety of standard flumes and weirs, or user programmable for a custom application, the Greyline OCF 5.0 allows simple irrigation flow monitoring and the ability to log flow data or output to another device.

Part Number Price Available
OCF 5.0A-1-A-1-D-1-A-2-A
Show Configuration
Base Price
Power Input
100-240VAC 50/60Hz
NEMA4X (IP66) fiberglass
Enclosure Temperature
Standard, -5 to 140°F (-20 to 60°C)
Electronics Protection
Standard, no circuit board coating
PZ15 level sensor, PVC, 8in deadband, 15ft range
Standard, general purpose locations, not rated Intrinsically Safe
Sensor Cable
25ft RG62AU coaxial
Control Relays
2, standard
$2,195.00 1

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