company news about Installation Specifications and Engineering Practice of Remote Water Meters: A Comprehensive Guide from Design to Acceptance

I. Preliminary Planning for the Implementation of Remote Water Metering Projects

(I) Demand Analysis and Scheme Selection classification design:

Residential users:

Prefer photoelectric direct reading (high precision) or LoRa pulse type (low cost), DN15-DN20, supporting tiered water price charging function (requiring built-in storage module in the meter). Industrial users: Use ultrasonic time difference method (DN5-DN300), configure RS-485/M-Bus interface, support instantaneous flow monitoring and abnormal flow alarm (such as triggering a warning when exceeding the flow by 150%). Renovation of old residential areas: Take into account the difficulty of wiring, choose wireless type (LoRa/NB-IoT, the meter body needs to adapt to the old pipeline interface (such as thread to flange converter), and reserve future upgrade space (such as supporting external temperature sensor).Communication network planning: Wired network (such as M-Bus bus): Suitable for new residential areas, the bus uses a star topology, each 32 water are equipped with 1 relay, total length ≤ 2400m, detailed pipeline drawings need to be drawn (indicating the physical address and wiring sequence of each meter). Wireless network: LoRa needs to plan the gateway position (1-2 per square kilometer), NB-IoT needs to confirm the signal coverage map with the operator, avoid installation in "signal blind areas" (such as basements, steel structure buildings).

(II) Equipment Procurement and InspectionQualification review: Water meters need to have CMC metrology

certification (China Manufactured Metrological Instruments Permit), CE/CB international certification, and for wireless, they also need a radio transmission equipment type approval certificate (SRRC certification). Sampling inspection ratio: When purchasing in bulk, 1% (no less than units) of each batch is sampled for full performance testing, including static pressure test (no leakage under 1.6MPa pressure for 15 minutes), electromagnetic compatibilityanti-radio frequency interference ≥ 10V/m). Pre-commissioning preparation: Simulate the on-site environment in the laboratory, encode water meter address (ensure no duplication), configure communication parameters (such as LoRa frequency point, spreading factor), and enter the asset management system to generate a unique QR identifier (including model, installation location, warranty period, etc.).

II.Standardized Operation Processes During Construction

(I) Site Survey and Positioning Pipeline Survey:

A laser rangefinder to record the pipeline direction, diameter, and valve positions, draw a three-dimensional sketch, mark the coordinates of the water meter installation position (precision ±5), and avoid conflicts with gas pipelines and cable trays (horizontal spacing ≥30cm, vertical spacing ≥10cm). For high-rise ris, it is necessary to confirm the water meter installation layer (usually in the equipment layer or intermediate layer) to avoid installation inside residents' rooms (for easy maintenance and to reduce disturb). Tool Preparation: Essential tools: pipe wrench, threading machine, heat fusion machine (PPR pipe), electric welding machine (steel pipe, torque wrench (torque calibration), signal tester (such as LoRa SNR detector). Safety equipment: safety helmet, anti-skid gloves, gas (when working in limited spaces, such as underground meter wells, it is necessary to detect oxygen concentration >19.5%, combustible gas concentration <5% of L).

(II) Key Points of Installation Construction Seven-step method for mechanical installation: ① Pipe cutting and cleaning: use a toothless saw to cut pipeline, grind the bevel to eliminate burrs; ② Valve installation: first install the upstream shut-off valve (≥10 times the diameter of the pipeline from the meter), then install the downstream check valve (only required when installed vertically); ③ Meter body fixing: align the flow direction mark, use the matching flange or thread connection, and symmetrically tighten the bolts (tighten in 2-3 times to ensure even force); ④ Sealing treatment: wrap with PTFE tape (thread connection) or add a sealing gasket (flange connection), and use soapy water to detect that there is no air bubble leakage at the interface; ⑤ Cable laying the wired bus is protected by PVC pipes, and the wireless meter is installed with an antenna (external antennas need to be fixed with stainless steel brackets, ≥2m from the); ⑥ Grounding treatment: metal meter cases need to be connected to the PE line (4mm² yellow-green wire), and the grounding resistance ≤1Ω (tested with a grounding tester); ⑦ Information posting: paste the user number, repair phone number, and last calibration date on the meter body for easy later. Special scene handling: Water meter well installation: a 10cm concrete cushion layer needs to be poured at the bottom of the well, the meter body is 30cm from the well cover, a 50cm×50cm maintenance space is reserved, and a moisture sensor is added to the well (alarm when humidity80%). Installation in the ceiling: use a detachable meter box (fire rating B1), reserve a maintenance hole (size ≥40cm×0cm), and mark the position on the ceiling drawing (to avoid damage during decoration).

III. Core Indicators for Debugging and Acceptance

(I) Functional Debugging Meter Testing: Metering Testing: Through standard meter method testing, the error is ≤±5% at low flow (Q1=0.03m³h) and ≤±2% at normal flow (Q3=3m³/h) (complies with GB/T 778-201). Communication Testing: Continuously send 100 instructions, with a reception success rate ≥99%, response time <10 seconds (wireless) or <2 seconds (wired type), signal strength LoRa≥-120dBm, NB-IoT≥-110dBm. Systeming: Cluster Testing: Select 50 water meters to form a minimum system, simulate peak hour data concurrent upload (20:00-22:00, detect concentrator processing capability (ideal concurrent number ≥200 units/second), packet loss rate <0.1%. Abnormal Simulation: Manually scenarios such as pipeline leakage (sudden increase in flow), battery under-voltage, signal interruption, etc., to verify the system's early warning mechanism (the should issue an alarm within 2 minutes).

(II) Engineering Acceptance Standards Data Archiving: As-built Drawing: Includes pipeline plan, system network diagram equipment list (including asset number and installation location coordinates of each water meter). Test Report: Includes key data such as single meter metering error, system communication success rate grounding resistance, etc., signed and confirmed by the construction party, the client, and the supervisor. Operation Manual: Write the "Guide for Operation and Maintenance of Water Meters", clarify daily inspection items (once a month, including meter appearance, signal strength, battery voltage) and fault handling process. Quality Spot Check: Me Part: No water leakage at the interface, no damage to the meter body, correct flow direction; Electrical Part: Solid wiring (pull-test ≥5N without off), grounding meets the requirements, communication module working temperature <50℃ (infrared thermometer detection). Spot check 10% of the installed water meters focusing on: IV. Typical Engineering Case: Large-scale Application of a Smart City Demonstration Area In the smart water project of a new district in Chengdu the installation and implementation of 30,000 sets of remote water meters (photoelectric direct reading NB-IoT hybrid network) were divided into three stages:Preliminary Preparation (1-2 months): Complete 1:500 topographic map survey, mark 200 pipeline well positions, and coordinate with gas electricity departments for cross-construction schemes. Customized development of the water management platform, pre-enter the three-dimensional coordinates of each water meter (connecting with the G system), to achieve real-time data display on the map. Construction Stage (3 months): Adopt "zonal construction flow operation", each construction equipped with 1 technician (responsible for signal debugging), 2 installers (responsible for pipeline and meter body installation), daily completion of 80 sets of water meter. For high-rise buildings, use UAVs to inspect the installation location of LoRa gateways on the rooftop, ensuring signal coverage radius ≥800m.Acceptance and Optimization (1 month): Find that 5% of water meters are blocked due to residual welding slag in the pipeline, which is solved by adding 10 front-mounted filters. For the underground garage area with weak NB-IoT signal, add 15 signal amplifiers, reducing the disconnection rate from 3 to 0.2%

Conclusion

The installation of remote water meters is a systematic project that integrates mechanical engineering, electronic communication, and metrology. From the preliminary scheme design to later operation and maintenance acceptance, each link needs to follow the standardized process. Through precise demand analysis, strict construction management, and scientific commissioning and acceptance, the long-term stable of remote water meters can be ensured, providing reliable data support for smart water affairs. With the advancement of the national "new urban construction" policy, the installation of remote water will be upgraded from single equipment construction to a "hardware software service" integrated solution, promoting the management of urban water resources towards digitalization and intelligence