1. Select the specifications of the water meter
When selecting the specifications, the water meter with the most common flow rate closest to the value should be selected as the first choice according to the size and range of the flow rate used under normal circumstances. Because the design of the water meter is based on the common flow rate, the stability and durability of the water meter's working performance under the common flow rate is the best, which is more in line with the design requirements.
If the minimum flow rate and the boundary flow rate are selected, different types of water meter range ratios (Q3 / Q1) are different, which will cause differences in common flow rates. This may cause the frequently used flow rate to be greater than the common flow rate of the water meter. The service life is greatly reduced.
2. Select the model of the water meter
Whether it is an ordinary water meter or a smart water meter, we must recognize the function classification of the water meter when purchasing, and according to the actual situation on the spot, choose the appropriate water meter or smart water meter. Common water meter types are: pointer type (denoted by C), pointer digital combination type (denoted by E), semi-liquid sealed type (denoted by Y), full liquid sealed type (denoted by F), dry type (denoted by G) ). According to the indicator type of the water meter, the word wheel type is generally better. The digital wheel of the liquid-sealed type counter or the entire counter is prepared with a certain concentration of glycerin, etc. to prepare a liquid-sealed water meter. The clarity of the sealed and isolated counter is not affected by the external water quality, and the reading is clear and easy to read. According to the practical functions of the water meter, it is divided into: ordinary mechanical water meters, intelligent water meters with electronic devices, and remote water meters are divided into wired remote transmission and wireless remote transmission. The prepaid smart water meter is a kind of water meter with a preset function composed of a common water meter as a base meter, a controller and an electric control valve added. The management of "paying money first, then using water" can be realized.
3. Consider the convenience of installation and maintenance
For large-caliber water meters, this is especially a consideration. Therefore, a kind of water meter (such as a detachable water meter) that can be installed and replaced or maintained without stopping water can meet these requirements. The installation length and connection method of the water meter are also a factor to be considered.
4. Consider the adaptability of water quality
For various reasons, the quality of the water flowing through the water meter and reaching the water terminal is not as clean as it is when leaving the water plant, and sometimes contains some impurities (such as rust, sand, hemp, etc.). In this case, in addition to considering the installation of some filters and other measures in the design of the pipeline of the water meter, the selection of a water meter or flow meter that can adapt to such water quality needs to be considered.
5. Cost performance
Any purchase of goods must consider their performance-price ratio. Under the premise of meeting the basic requirements of the water meter verification regulations or the first verification of the water meter, the materials used in the water meter are hygienic and durable, reliable and convenient to read, the size of the pressure loss, the convenience of maintenance and disassembly, and the adaptability to the installation site (If it may be installed outdoors) is the main performance of the water meter.
In summary, the selection of water meters can be considered from the following points:
(1) Accurate and reliable measurement;
(2) Adapt to the water quality conditions of the pipe network, durable;
(3) Simple structure and high cost performance;
(4) Large circulation capacity and small pipeline pressure loss;
(5) Easy to repair, easy to adjust, and low maintenance cost;
(6) The meter reading is accurate and convenient, and is compatible with local management.
Some of the above factors are contradictory. When choosing, the pros and cons should be analyzed in conjunction with the actual situation.