Product Overview:

A photoelectric direct reading meter is a type of water meter that prints specific marks on the outer edge of the counter wheel at positions 0-9, and fixes photoelectric sensors and related circuits on its periphery. When reading the meter with external power supply, the status of specific marks "yes" and "no" is determined by a photoelectric sensor, and the reading of the character wheel (the window value of the meter) is obtained by combining coding.

1. Principle:

It is achieved by establishing a mathematical model of the character wheel, combining calculations to find the unique and correct solution, and then printing specific marks on the corresponding positions of 0-9 of the character wheel according to mathematical laws. Fixed photoelectric sensors are then installed around them according to mathematical laws, thus realizing a mathematical problem through electronic circuit methods. By considering various redundant and error correcting algorithms simultaneously, a unique and correct solution can be obtained - that is, the unique data on the character wheel. At present, there are two main types of direct reading meters that use this method: photoelectric reflection (transmission) and photoelectric reflection. The main difference lies in the mechanical structure and mathematical algorithm. The photoelectric reflection type is a method of installing photoelectric devices and circuit boards between the character wheels, while the photoelectric reflection type is a method of installing light around the character wheels

2. Characteristics:

1) Directly reading the counter code disk number of the meter, which is the "window value", does not require setting parameters such as the base number and table constant in the table, does not require storing data, and there is no cumulative error. It truly realizes "reading the meter" and ends the history of cumulative pulses and converted values. The electronic part of the direct reading instrument is completely separated from the counter and other devices inside the instrument without mechanical contact, which does not affect the measurement accuracy.

2) The direct reading remote transmission meter directly transmits data, rather than pulse signals. It is not only unaffected by mechanical vibrations, but also has extremely high anti-interference ability against electromagnetic interference, so it can achieve stable, accurate, and reliable measurement in complex usage environments.

3) Direct reading remote meters do not require power supply for daily operation, which is a revolutionary technological advancement that avoids measurement errors and extensive maintenance work caused by unstable or faulty power supply.

4) Due to the fact that the direct reading remote meter collects the position of the mechanical counter wheel (rather than the pulse), when the meter is reversed, the meter reading data still remains consistent with the reading of the primary meter.

3. Advantages

1) In terms of measurement performance: As the photoelectric sensor is a non rotating part fixed inside the meter, it does not come into contact with any mechanical rotating parts and only collects signals through light emission and reflection. Compared with resistance direct reading meters, it has no damping and does not affect the measurement performance of the meter. Therefore, there will be no disputes regarding measurement.

2) In terms of manufacturing process, due to the use of distributed photoelectric sensors around the character wheel, this part can be independently manufactured and then installed inside the meter without affecting the meter structure. The production process is simple, easy to assemble, and suitable for large-scale production. And this part can be tested separately, ensuring the reliability of the product.

3) In terms of long-term operation: As it does not come into contact with the mechanical rotating part of the meter, it will not affect the meter's long-term operation. At the same time, the photoelectric sensor does not work normally and is not powered, thus greatly extending its lifespan. The reliable working time of electronic components far exceeds the service life of mechanical meters. So, it is suitable for long-term operation and repeated use.

4) In terms of module universality, the character wheel direct reading part of the photoelectric direct reading meter can be made into an assembly, including the character wheel with special markings, the dial clamp plate, and the electronic part. This assembly can be manufactured by specialized manufacturers in one go and can adapt to most dry and liquid sealed water meters in China. Therefore, it has good universality, strong processability, and strong adaptability.