Host Dimension :(unit: mm, including waterproof connectors)
Probe Dimension：(unit: mm)
Model: GLP-5A MOQ: 1 qty
Commonly Used Water Weirs and Flumes and Their Flow Measurement Ranges
Thin-plate weirs are mainly divided into three types: triangular notch weir, rectangular notch weir and uniform-width weir. Broad-crested weirs are mainly divided into two types: rectangular broad-crested weir and round-edged broad-crested weir.
| Category | Weir / Flume Type | Flow Measurement Range |
|---|
| Thin-plate weir | Triangular notch thin-plate weir | 0.2×10⁻³ ~ 1.8 m³/s |
| Thin-plate weir | Rectangular notch thin-plate weir | 1.4×10⁻³ ~ 49 m³/s |
| Thin-plate weir | Uniform-width thin-plate weir | 0.8×10⁻³ ~ 77 m³/s |
| Broad-crested weir | Rectangular broad-crested weir | 8×10⁻³ ~ 65 m³/s |
| Broad-crested weir | Round-edged broad-crested weir | 8×10⁻³ ~ 820 m³/s |
| Profile weir | Triangular profile weir | 3×10⁻³ ~ 1300 m³/s |
| V-shaped weir | Flat V-shaped weir | 14×10⁻³ ~ 630 m³/s |
| Flume | Parshall flume | 0.1×10⁻³ ~ 93 m³/s |
| Flume | Cut-throat flume | 0.7×10⁻³ ~ 3.0 m³/s |
Terminal Wiring Diagram
Terminal Section Description
L, N, and ground are AC220V power input terminals (DC power supply is not connected).
NO, COM, NC are control switch output points (lower control L, upper control H).
mA+, mA- is 4-20mA current signal output.
DCIN+, DCIN- are DC power input terminals.
TRX+ and TRX- are RS485 signal outputs.
S-RFZ, S-RFW probe terminals (special probe wiring): S-RFZ probe coaxial cable center head; S-RFW probe coaxial cable shield.
VCC, GND, IN, OUT probe terminals. Please connect with the corresponding connection, generally using a 4×0.5 shielded cable.
Installation Diagram
Schematic (1)
Schematic (2)
Level height: water level, starting from zero ⑦.
Current air distance: probe to the area of the measured surface ⑥.
Instrument blind zone: a small area below the launch surface ⑤.
Product Size (Unit: mm)
Introduction, Common Faults and Solutions of Ultrasonic Open Channel Flowmeter
(1) Product Introduction
The ultrasonic open channel flowmeter adopts ultrasonic detection technology to measure the flow velocity and flow rate of open channel water. The sensor installed in the river channel transmits ultrasonic signals and calculates the water flow velocity and flow rate by receiving the reflected ultrasonic echoes.
Equipped with a programmable controller, the instrument supports remote monitoring, automatic control and data transmission, which effectively improves measurement accuracy and operation efficiency. It is widely applied in water conservancy, river hydrology, environmental protection and sewage monitoring fields.
(2) Common Fault Causes
2.1. Unstable signal strength and inaccurate data
Strong electromagnetic interference from on-site frequency converters and high-power motors, poor equipment grounding, turbulent water flow, surface waves, bubbles and false reflections will cause disordered ultrasonic echoes and fluctuating signal strength, resulting in inaccurate measurement data.
2.2. Influence of air and sundries in the water channel
Air bubbles, floating impurities and sediment in the water medium interfere with ultrasonic signal transmission and affect the normal measurement results.
2.3. Sensor wear, dirt and aging
Long-term operation may cause sensor contamination, abrasion and performance degradation, leading to reduced sensitivity, poor signal coupling, decreased measurement accuracy or equipment failure.
2.4. Improper installation and parameter setting
The probe is not installed vertically; unreasonable installation position causes acoustic dead zones. Wrong settings of pipe diameter, sound velocity and channel parameters, as well as lack of regular zero and range calibration, will lead to measurement deviation.
2.5. System transmission and operation errors
Non-standard operation, incorrect system configuration and abnormal signal transmission will cause data abnormality or system failure.
(3) Solutions and Maintenance Measures
3.1. Stabilize signals and eliminate electromagnetic interference
Implement reliable independent grounding for the equipment. Adopt shielded signal cables and isolated power supplies to reduce electromagnetic interference. Install wave guides or flow rectifiers to stabilize the flow field and reduce the influence of water waves and bubbles.
3.2. Optimize on-site measuring conditions
Clean up air bubbles, floating sundries and sediment in the channel to ensure a stable and clean measuring environment. Select a stable water area for reinstallation and avoid turbulent and dead zones.
3.3. Strengthen daily sensor maintenance
Regularly clean the sensor surface, adjust the vertical installation angle, and apply ultrasonic coupling agent properly. Replace worn or aging sensors in time to ensure detection sensitivity.
3.4. Correct parameters and perform regular calibration
Verify and correct parameters such as pipe diameter and sound velocity. Conduct regular zero point and range calibration to eliminate systematic errors.
3.5. Standardize operation and data management
Operators shall be familiar with system operation specifications. Timely inspect and handle abnormal data to ensure stable system operation and normal data transmission.
Installation & Maintenance
Gallop Ultrasonic Open Channel Flow Meter is designed for easy installation and efficient maintenance. It can be quickly mounted in various open channel environments, with simple wiring and an intuitive setup procedure for rapid deployment. Its accessible components and user-friendly interface make regular maintenance easy, requiring only minimal time and effort, such as periodic cleaning of the ultrasonic transducers.
Frequently Asked Questions (FAQs)
Q: What types of open channels can your meters measure?
A: Any non-full flow channel using a flume or weir, including Parshall, V-notch, rectangular, and trapezoidal weirs.
Q: Do I need to build a flume for accurate readings?
A: Yes, flow rate is calculated from water level and channel geometry. A flume or weir is required for volume accuracy.
Q: Can I get data remotely?
A: Yes, models support Modbus RTU, RS485, and wireless (GPRS/4G) communication.
Q: What is your MOQ for wholesale orders?
A: MOQ for wholesale pricing is 10 units. For OEM, MOQ is 30–50 units depending on customization.
Q: Do you offer calibration support?
A: Each unit is factory calibrated. We can also provide simulated calibration reports or local partner assistance.
