Product Background

In order to implement the Environmental Protection Law of the People's Republic of China and the Water Pollution Prevention and Control Law of the People's Republic of China, protect the ecological environment, and safeguard human health, the Ministry of Ecology and Environment issued the "Technical Specifications for Installation of Online Monitoring Systems for Water Pollution Sources (CODCr, NH3-N, etc.)" and "Technical Specifications for Acceptance of Online Monitoring Systems for Water Pollution Sources (CODCr, NH3-N, etc.)" on December 24, 2019. In the "Installation Technical Specification", it is proposed that a flow monitoring unit is required in the composition of the online monitoring system. For the discharge units that need to measure flow, standardized measuring weirs (troughs) should be built for open channels, and the construction of weirs should be able to compare open channel flow meters. Triangular weirs, rectangular weirs, and Bacher troughs are recommended. In the "Acceptance Technical Specification", specific requirements are proposed for the acceptance method of water pollution source flow monitoring units, which are divided into liquid level error comparison and flow error comparison, as follows:

(1) Liquid level error comparison: Use a portable open channel flow meter comparison device and an ultrasonic open channel flow meter to measure the liquid level values at the same water level observation section, conduct a comparison test, record the data pairs every 2 minutes for 6 consecutive times, calculate the error value Hi of each data pair, and select the maximum Hi as the liquid level comparison error of the flow meter.

(2) Flow Error Comparison: Use a portable open channel flow meter comparison device and an ultrasonic open channel flow meter to measure the instantaneous flow at the same water level observation section for comparison experiments. After the data is stable, start timing for 10 minutes. Read the cumulative flow F1 of the open channel flow comparison device and the cumulative flow F2 of the ultrasonic open channel flow meter during this period, and calculate the flow comparison error Δ F according to the formula.

The portable open channel flowmeter, based on the JJG711-1990 calibration regulation and referring to the comparison and acceptance of flow monitoring units in HJ353-2019, HJ354-2019, and HJ355-2019, can automatically collect data every 2 minutes, continuously record 6 times of data for liquid level error comparison with online flowmeter data, and automatically measure flow data within 10 minutes for flow error comparison with online flowmeter data. At the same time, the results can be automatically generated into a comparison report for printing or querying.

Functional Features

(1) Suitable for four basic weir types: triangular weir, rectangular weir, equal width weir, and Bacher trough;

(2) High precision signal acquisition module, 24 bit acquisition accuracy, measurement data is true and effective;

(3) Large screen color LCD touch screen, touch operation, key data password protection;

(4) The curve displays the trend of flow rate and liquid level changes;

(5) A friendly human-computer interaction interface, combining graphics and text, allowing for instrument operation without the need for professional knowledge;

(6) The instrument is equipped with a micro printer, which can directly print measurement data on site;

(7) Can be connected to a computer to output measurement data to the computer, making it easy for users to perform statistical analysis on the data;

(8) Can store 10000 measurement history records;

(9) Equipped with a large capacity lithium battery, it can measure continuously for 72 hours on a single charge;

(10) The flowmeter is equipped with an intelligent power management system, which extends the battery life;

(11) Handheld box design, lightweight and convenient for users to carry, with a waterproof rating of IP65.

TECHNICAL INDEX

(1) Flow measurement range: 0-40m3/S;

(2) Flow measurement frequency: 3 times/second;

(3) Liquid level resolution 0.1mm,

(4) Liquid level measurement error: ≤ 0.5mm；

(5) Sensor range: 1 meter (standard) 2 meters (optional)

(6) Flow measurement error: ≤ ±1%；

(7) Signal output mode: USB；

(8) Working environment humidity: ≤ 85%；

(9) Working environment temperature: - 10℃～＋50℃；

(10) Working power supply: AC 220V ± 15%;

(11) Built in battery: DC+16V lithium battery, battery powered continuous working time: 72 hours;

(12) Dimensions: 395mm × 295mm × 110mm;

(13) Whole machine weight: 4Kg.

Site installation

Portable open channel flowmeter, easy and fast to install on site; Comparison is easy and fast, just enter on-site data.

Case photos

TECHNICAL INDEX

(1) Flow measurement range: 0-40m3/S;

(2) Flow measurement frequency: 3 times/second;

(3) Liquid level resolution 0.1mm,

(4) Liquid level measurement error: ≤ 0.5mm；

(5) Sensor range: 1 meter (standard) 2 meters (optional)

(6) Flow measurement error: ≤ ±1%；

(7) Signal output mode: USB；

(8) Working environment humidity: ≤ 85%；

(9) Working environment temperature: - 10℃～＋50℃；

(10) Working power supply: AC 220V ± 15%;

(11) Built in battery: DC+16V lithium battery, battery powered continuous working time: 72 hours;

(12) Dimensions: 395mm × 295mm × 110mm;

(13) Whole machine weight: 4Kg.