Smart Water Conservancy

Water Resource Tax Intake Metering & Online Monitoring Solution

Q: LGF-PA66 electromagnetic flow meter vs turbine flow meter: which one should I use for clean water?

Both meters handle clean conductive water, but their construction leads to very different field behavior. Turbine meters use an impeller in the flow path to generate pulses. They are accurate (±0.5%–±1.0%), but the rotor is a wearing part: particles, scale and rust can jam it, low flow may never overcome bearing friction (a dead start-up band), and the constriction creates permanent pressure loss. On raw water carrying algae or floc, turbine bearings typically last only 1–2 years. The LGF-PA66 electromagnetic flow meter has an unobstructed measurement tube with no moving parts — only the liner and electrodes touch the medium. It is immune to particles and fibers, pressure loss is near zero, turndown reaches 100:1, and accuracy holds at velocities down to 0.3 m/s, which matches the strong day/night flow swings of supply networks. The aviation-grade PA66 composite body is roughly 60% lighter than a stainless body of the same size, cannot corrode, and the IP68 design allows submerged pit installation. Turbine meter: small-bore (DN4–DN40) batching of oil products or ultra-pure water. LGF-PA66: DN15 and above for potable water, reclaimed water and industrial water — especially custody-transfer points and DMA district meters. For more details, please visit our product page or contact our technical team.

Q: How should I choose between the 0.2% and 0.5% accuracy versions of the LGF-PA66 electromagnetic flow meter?

The LGF-PA66 is produced in both ±0.2% and ±0.5% accuracy versions. The choice depends on what the flow data is used for — not on picking the highest number. ±0.5% version : for process monitoring, internal water balance in wastewater plants, industrial cooling-water assessment and most DMA district meters, where readings guide operations rather than invoices. Paired with an EC32 RTU uploading instantaneous flow and pressure for night-flow leakage analysis, it is fully sufficient — and saves a price tier. ±0.2% version : for custody transfer and billing (water sales between companies, heat-supply metering), quota-based assessment, and any point verified under JJG 1033, the Chinese verification regulation for electromagnetic flow meters. On large lines a 0.3% error translates into a substantial annual billing difference. Two engineering details matter in practice. Rated accuracy holds within the 0.3–5 m/s velocity window — if the line runs persistently below 0.5 m/s, downsize the meter to raise velocity, otherwise neither version performs. The ±0.2% version is also less tolerant of installation disturbances: keep at least 10D straight pipe upstream and 5D downstream, away from pump-outlet turbulence. The integral PA66 body with built-in grounding electrode closes the signal loop inside the meter, which is what keeps the zero stable at high turndown. Specify the accuracy grade at order time — the two versions differ in converter calibration and are not interchangeable in the field. For more details, please visit our product page or contact our technical team.

Q: How to configure the LGF-PA66 with an EC32 RTU for a DMA district metering point? Which communication protocols are supported?

The standard DMA district metering point is an LGF-PA66 magnetic flow meter plus an EC32 RTU plus minimum-night-flow analysis on the platform side. There are two wiring options: connect the LGF-PA66 RS485 port to the EC32 serial port over shielded twisted pair running Modbus RTU (default 9600bps, 8N1), or feed a 4-20mA analogue signal into an EC32 AI channel. For long cable runs prefer the digital link — better noise immunity, and it also exposes totaliser, empty-pipe alarms and other diagnostics. Configuration points: Addresses and registers : when several LGF-PA66 meters share one RS485 bus, assign each a distinct slave address, poll instantaneous and totalised flow registers, and verify the unit scaling factors. Acquisition strategy : set the EC32 to sample every minute and report every 15 minutes. The 2:00–4:00 minimum-night-flow window must never be skipped — it is the core input for leakage analysis. Connectivity : the EC32 supports 4G Cat.1 and NB-IoT. In underground valve chambers with weak signal, order the external-antenna version and route the antenna to the chamber mouth. On the platform, alarm thresholds are set against the baseline of minimum night flow, combined with district pressure data to locate leaking pipe sections. Meter sizes follow the district main — commonly DN80 to DN300 — with flange standards matched to the existing network. For more information, please visit our product pages or contact our technical team.

Q: Should an electromagnetic flow meter be installed on the pump suction or discharge side? LGF-PA66 siting in pump stations

Install it on the discharge side whenever possible. On the suction side the meter sits under vacuum, where cavitation and degassing cause erratic readings, the flow profile is disturbed by elbows and reducers, and sustained vacuum stresses the flange-to-body seal. The LGF-PA66 has an all-insulated composite body with no liner to debond, but the positive-pressure siting rule still applies. Siting checklist for pump stations: Straight run ≥5D upstream and ≥2D downstream; extend the upstream run if a reducer sits close; Avoid the highest point of the line (air pockets) and the lowest point (sediment); prefer a mid horizontal run or a vertical section with upward flow; Flooded valve pits require the IP68-rated version; the PA66 body weighs about half of a comparable stainless-steel meter, which matters when lowering it into a confined pit; With frequent pump cycling the PA66 body withstands water-hammer shocks well, and an EC32 RTU can alarm on flow transients to watch pump health. If suction-side mounting is unavoidable, confirm the pump runs flooded-suction and keep the meter as close to the pump inlet flange as possible to shorten the vacuum section. Check pipe supports before installation — vibration from the pump outlet travels into the meter body and affects long-term sealing. For more information, please visit our product pages or contact our technical team.

Q: What is the pressure loss of the LGF-PA66 electromagnetic flow meter and does it add pumping energy cost?

The LGF-PA66 has a full-bore straight-through measuring tube with no throttling elements and no moving parts. Pressure loss comes only from minor local resistance: a few kPa up to roughly a dozen kPa at rated flow across DN15–DN1200. Orifice plates typically cost 10–40 kPa and turbine meters are comparable or worse, so the electromagnetic design is the energy-saving choice. Two points for pumping-cost evaluations: The PA66 body is moulded in one piece with low surface roughness; at the same size and flow it loses slightly less head than a stainless-steel body with a separate liner; In pump-station retrofits this pressure-loss level barely shifts the system resistance curve, so the pump operating point and long-term electricity consumption stay effectively unchanged. Where energy KPIs matter, pair the LGF-PA66 with an EC60 RTU: it collects the meter's 4–20 mA or pulse output together with pump power data and computes specific energy (kWh per m³) for the platform, exposing high-consumption periods. On DN300+ lines, every kPa of head saved translates into thousands of kWh per year — the reason many municipal stations replace orifice metering with the LGF-PA66 during upgrades. For more information, please visit our product pages or contact our technical team.

An online water intake metering solution based on electromagnetic flowmeters and clamp-on ultrasonic flowmeters, helping water users achieve precise metering, automatic reporting, and tax compliance under China's Water Resource Tax Reform.

Overview

Summary

Key Advantages

Multi-diameter coverage: DN50-DN2000 full pipe range, dual technology (EMF + clamp-on ultrasonic)

Zero-downtime installation: clamp-on ultrasonic flowmeter requires no pipe cutting, installation <4 hours

Tamper-proof design: RTU with built-in encrypted storage, timestamped and digitally signed data, irreversible

Multi-protocol integration: supports MQTT, Modbus TCP, HTTP/JSON and other mainstream industrial protocols

Remote O&M: OTA firmware upgrades, remote parameter configuration, and fault self-diagnostics

Challenges

Scattered intake points and aging pipelines make installation difficult
Policy requires minute-level real-time data reporting — manual methods cannot comply
Multi-system integration: simultaneous data push to water and tax platforms with non-uniform interface standards
Intake data must be tamper-proof and traceable for tax audit purposes
Different intake types (surface/groundwater) apply different tax rates with complex calculation logic

Results

Metering accuracy better than 0.5%, meeting national standard requirements
Data reporting success rate ≥99.5%, daily data completeness 100%
Zero data loss during communication interruptions, automatic backfill after restoration, up to 30 days offline caching
Per-site construction cost reduced by 30%+ compared to traditional approaches
Full-process automation from intake metering to tax filing, reducing manual intervention by 90%

Solution Details

Overview of the Water Resource Tax Intake Metering & Online Monitoring Solution

With the nationwide implementation of China's Water Resource Tax Reform Pilot Measures, water intake users are required to install metering facilities that meet national standards and upload intake data in real time to tax and water regulatory platforms. Traditional manual meter reading can no longer meet the policy requirements for online monitoring, data tamper-proofing, and remote supervision — necessitating a low-cost, high-reliability, easy-to-deploy intake metering solution.

This solution adopts a dual-technology metering system combining inline electromagnetic flowmeters and clamp-on ultrasonic flowmeters to accommodate different pipe diameters and installation conditions. For new pipelines or intakes where shutdown is feasible, inline electromagnetic flowmeters deliver high-precision metering. For aging networks where shutdown or pipe cutting is prohibited, clamp-on ultrasonic flowmeters enable non-intrusive, zero-downtime installation. All metering data is centrally collected, stored, and transmitted via the Hero V9 RTU telemetry terminal.

Core Technical Advantages of the Intake Metering Solution

The system supports 4G/5G/NB-IoT multi-mode communication, with built-in store-and-forward and data encryption capabilities ensuring zero data loss even during communication interruptions. The RTU features local storage (≥16GB) capable of caching over 30 days of minute-level data, with automatic backfill upon communication restoration. Front-end data acquisition frequency reaches once per minute, meeting the time granularity requirements of tax authorities.

At the data reporting layer, the system interfaces via standardized APIs with the Ministry of Water Resources' intake metering monitoring platform, provincial water resource management systems, and the tax authority's Golden Tax System, enabling automatic data push, anomaly alerts, and filing assistance. The solution includes a water resource tax calculation model that automatically computes tax liability based on intake type (surface water/groundwater), industry category, and regional tax rates — achieving full-process automation from metering to tax filing.

Key Performance Metrics & Validation

0.5%

Per-site Metering Accuracy

≥99.5%

Data Reporting Success Rate

100%

Daily Data Completeness

The solution has been validated across multiple provinces and cities, achieving per-site metering accuracy better than 0.5%, data reporting success rate ≥99.5%, and daily data completeness of 100%.

Technical Specifications & Product Features

Multi-diameter coverage: DN50-DN2000 full pipe range, dual technology (EMF + clamp-on ultrasonic)
Zero-downtime installation: clamp-on ultrasonic flowmeter requires no pipe cutting, installation <4 hours
Tamper-proof design: RTU with built-in encrypted storage, timestamped and digitally signed data, irreversible
Multi-protocol integration: supports MQTT, Modbus TCP, HTTP/JSON and other mainstream industrial protocols
Remote O&M: OTA firmware upgrades, remote parameter configuration, and fault self-diagnostics

Application Scenarios for the Water Resource Tax Monitoring System

This solution is ideal for industrial water users, agricultural irrigation districts, municipal water supply companies, and any entity subject to water resource tax regulations. It is particularly suited for scenarios requiring retrofitting of existing intake points where pipe cutting is not feasible, as well as new installations demanding high-precision, real-time data transmission to government platforms.

Approach

How we implement intelligence into your infrastructure step by step.

Site Survey & Instrument Selection

Evaluate intake pipe diameter, material, water quality, and installation conditions. Select either an inline electromagnetic flowmeter or clamp-on ultrasonic flowmeter and determine the optimal installation location and metering well retrofit plan.

Metering Equipment Installation & Commissioning

Complete flowmeter flange connection or sensor clamping, RTU control cabinet installation, power supply and grounding system construction. Conduct on-site calibration and communication testing to ensure metering accuracy and communication link reliability.

Communication & Data Platform Integration

Configure RTU communication parameters and test 4G/5G/NB-IoT channel quality. Complete API-based data integration and joint debugging with the Ministry of Water Resources platform, provincial water resource systems, and the Golden Tax System.

Water Resource Tax Calculation Setup

Configure tax calculation models and filing rules based on water intake permit type, usage category, and regional tax rate policy. Validate computational accuracy and data synchronization with the tax system.

O&M Training & Go-Live

Train intake operator personnel on system usage, deliver O&M manuals and emergency response procedures. Set data anomaly alert thresholds and activate 7×24 remote monitoring. Official system go-live.