Optoelectronic direct reading of remote water meters (Level)

This water meter is a flow measuring instrument used to measure the total volume of water flowing through the tap water pipeline. The base meter is a detachable horizontal spiral wing dry water meter (optional with horizontal rotor and vertical spiral wing base meters).

feature

• 1. Directly reading the character wheel data, without cumulative errors, unaffected by jitter, and basically achieving "zero" error reading.

• 2. Adopting a low-power design, there is no internal power supply, and it does not consume electricity during normal operation. It only provides instant power supply when the temperature is low.

• 3. The intelligent electronic unit is completely sealed in the counter and is not corroded by external water and moisture.

• 4. Adopting advanced data encoding and verification methods, the communication reliability is high.

• 5. Adopting bus mode, the system engineering installation is simple and convenient, with less maintenance and cost savings.

• 6. Meet the design requirements for electromagnetic compatibility of electronic products such as EMC, ESD, EMI, etc., and achieve industry-leading levels.

• 7. Adopting fault diagnosis shutdown technology to ensure the security of the entire network.

• 8. Flexible networking with the upper computer system allows for remote automatic meter reading and manual centralized meter reading.

• This water meter complies with the standards of GB/T778.1-3-2007.

Terms of Use

• Temperature rating: T30 T30/90

• Flow profile sensitivity level: U10 D5

• Accuracy level: Level 2

• Pressure loss level: Δ p63

• Pressure rating: 1MPa 1.6Mpa

• Working power supply: DC10-24V (RS485); DC32-42V（M-BUS)

• Working environment: temperature ranging from 0.1 ℃ to 80 ℃ (maximum temperature of 30 ℃ on the cold water meter) and humidity; 0~95％RH

• Communication method with the upper computer: a) RS-485 fieldbus; b) M-BUS fieldbus;

• Working current: ≤ 5mA (RS-485); ≤10mA（M-BUS)

• Communication transmission rate: 1200/2400/9600 bit/s;

• Maximum communication transmission distance: 1200m;

• Communication protocol; Provide internal custom protocols, Ministry of Electric Power DLT645 (1997) protocol, CJ/T188 protocol (Ministry of Construction Universal Household Meter Communication Transmission Protocol).

• Bus pin ESD protection exceeds 10KV;

• Short circuit current limitation, bus open circuit, short circuit, idle and other fault protection.

Main technical parameters

Maximum allowable error:

1. Maximum allowable error in the low zone:

When the water temperature is within the specified range of rated working conditions, the maximum allowable error of the volume discharged between the minimum flow rate (Q1) and the boundary flow rate (Q2) (excluding Q2) is ± 5%.

2. Maximum allowable error in the high zone:

The maximum allowable error of the volume of flow discharged between the boundary flow rate (Q2) (including Q2) and the overload flow rate (Q4):

——± 2% when the water temperature is ≤ 30 ℃;

——When the water temperature is above 30 ℃, it is ± 3%.

Overall dimensions

wiring diagram

Selection, installation, and use of water meters

1. It is recommended to determine the type, measurement characteristics, and diameter of the water meter based on the working conditions of the water supply facilities. The expected flow rate should be compatible with the Q1 to Q3 flow rates of the water meter.

2. The installation of the water meter must follow the instructions on the water meter dial: the "H" mark indicates horizontal installation, and the "V" mark indicates vertical installation. The direction of the arrow on the watch case should be consistent with the direction of water flow in the pipeline.

3. Install plugs or globe valves upstream and downstream of the water meter, and install straight pipe sections of sufficient length and the same diameter according to the requirements of U10, D5 (10DN, 5DN) to ensure accurate measurement.

If necessary, a filter can be installed between the upstream valve and the straight pipe section, and a check valve can be installed between the downstream straight pipe section and the valve.

5. It is necessary to prevent damage to the water meter caused by the impact and vibration of the surrounding environment of the installation site.

6. The water meter should avoid excessive stress caused by pipes and fittings. When necessary, the water meter should be installed on a base or bracket. The upstream and downstream water pipes should be properly fixed to ensure that no part will shift due to the pushing force of water when removing the water meter or disconnecting one side connection.

7. Necessary water meter connection length should be left for pipeline installation. When the distance between the two ends of the pipeline exceeds the length of the water meter, the pipeline spacing should be corrected to meet the length of the water meter connection. Otherwise, if the spacing is too large, forced installation will cause the threaded connection end, pipe joint, connecting nut, and connecting flange of the water meter to break and be damaged. If the spacing is too small, the water meter cannot be installed. If the pipelines at both ends of the water meter are not on the same axis, other means should be used to correct the pipelines to be on the same axis to meet the installation requirements of the water meter. Otherwise, the above phenomenon may also occur. In order to compensate for length errors during water meter installation and facilitate water meter disassembly, it is recommended to use expansion joints with corresponding diameters downstream of water meters with Q3 ≥ 16m3/h.

8. Before installation, the pipeline should be flushed to prevent debris such as stones and mud from entering the water meter.

To ensure long-term operation of the water meter, it should always be filled with water, and it is recommended that the outlet be at least 0.5m higher than the water meter.

10. Measures should be taken to prevent adverse hydraulic conditions (cavitation, surges, water hammer) from damaging the water meter.

11. Water meters should be protected from exposure to sunlight and freezing, and anti freezing measures should be taken during freezing periods. External environmental corrosion should be prevented from causing damage to the water meter.

During long-term use, water meters should be periodically calibrated according to local requirements. If there are debris, rust or other sediments blocking the water filter in the pipeline, which affects accurate measurement, it is necessary to recalibrate the water meter through a designated department. Users are not allowed to repair the water meter at will.