A water meter is an instrument for measuring water flow. It is mainly used for measuring the cumulative flow of water. Its core principle is to achieve measurement by driving internal mechanical or electronic components through water flow.

1. Structure and working principle

1. Traditional mechanical structure

It consists of three parts: shell, sleeve and inner core. Water flows into the lower ring chamber from the water inlet, and forms a rotating water flow through the water inlet hole in the tangential direction to impact the impeller. The impeller rotates and drives the counting device to display the cumulative water volume through the gear transmission.

- Key components: impeller (core drive element), gear set (transmission mechanism), water filter (blocking impurities).

- Metering terms: minimum flow (Q1), boundary flow (Q2), common flow (Q3), overload flow (Q4), corresponding to different measurement accuracy ranges.

2. Smart water meter technology

It integrates microelectronics, sensors and IC card technology to support remote data transmission, automatic ladder water price calculation and water use control. For example:

- NB-IoT Internet of Things meter: wireless transmission of water consumption data to achieve remote monitoring;

- IC card prepaid meter: use after recharging, and automatically cut off water when the balance is exhausted.

3. Key points for use and maintenance

1. Correct reading method

- Pointer type: read the pointers of thousands (×1000), hundreds (×100), tens (×10), and units (×1) counterclockwise, and take the value close to the smaller number.

- Digital type: black numbers are integer tonnage, and red numbers are decimal places (ignorable).

- Smart meter: data can be queried in real time through the APP.

2. Regular replacement and inspection

- Service life: water meters should not exceed 6 years, and they must be replaced free of charge upon expiration to avoid measurement deviations due to aging.

- Abnormal detection: If the water meter rotates or moves too fast, it is necessary to check for pipe leakage, valve sealing, or water use habits (such as long-term running water).

3. Installation specifications

- Horizontal installation, the arrow direction is consistent with the water flow, and 10D/5D straight pipe sections (D is the diameter) are retained upstream and downstream to avoid exposure to sunlight and freezing.

- Newly installed pipes need to be flushed of impurities to prevent clogging of the movement.