With the continuous development of science and technology, magnetic stick relay also obtained fast development, magnetic relay is developed in recent years, a new type of relay, has, magnetic high efficiency, small size, simple structure, convenient assembly, etc, used in satellites, missiles, spacecraft, aircraft and other equipment of the relay.
Along with the development of watt-hour meter, magnetic stick relay has become an important and indispensable part of watt-hour meter, to cooperate the installation and use of watt-hour meter, requirements of its small size, load capacity, input and output isolation degree is high, low consumption, low temperature rise, its main technical indicators are also because of the use of different environment, to keep magnetic relay setting, reset voltages, contact circuit, medium pressure, the power consumption of the coil, and the impact current, terminal temperature rise have higher requirements, ensure the reliability and security, and this means that the magnetic stick relay manufacturing process, material, quality control of tooling, etc.
At present, the largest market of industrial magnetic latching relays is the mid-end market, accounting for about 70% of the overall market share of industrial magnetic latching relays in the mainland. At present, there are fewer enterprises in the high-end market. The representative companies are Siemens and Phoenix. Customers in the mid-end market have certain requirements for product quality, are sensitive to price, and pay close attention to the brand of industrial magnetic latching relay. Therefore, most of the leading enterprises in the mid-end market are foreign-funded enterprises with good brand reputation and high product cost performance.
The research on the protection of microcomputer magnetic latching relay started in the late 1970s. After more than 20 years of development, the domestic computer protection technology progress, in the computer protection hardware, software, algorithms and other aspects have made a lot of achievements and patents, has launched four generations of computer protection device, the performance and operation index has been comprehensive beyond the imported products, in the international leading position. Domestic microcomputer protection has replaced transistor, integrated circuit protection, occupy the leading position.  
The Internet of Things and smart city will be one of the most important application markets of magnetic latching relay. Its application will penetrate into all aspects of future life, such as fire monitoring of power facilities in forests and mines. Extraction, tracking and monitoring of images of people and objects; Monitoring of video, optical fiber, gas, temperature and humidity in the intelligent building.
The technology of magnetic latching relay presents the characteristics of single function and develops towards the direction of intelligence and integration. With the rapid development of the Internet of Things, smart city and other application markets, higher requirements have been put forward for magnetic latching relay products in terms of low power consumption, reliability, stability, low cost, miniaturization, miniaturization, compound type, standardization and other technical and economic indicators.
The development of magnetic latching relay protection technology is closely related to the development of electronics, information and communication technology. In the future, with the gradual application of electronic CT(current transformer) and PT(voltage transformer), and the further improvement of IEC61850 standardization protocol, it can be predicted that digital technology will be more widely used. Domestic 110 kv, 220 kv voltage class of electronic type CT, electronic PT put into trial operation, research and development applicable to electronic CT and PT relay protection equipment, will promote the development of relay protection technology, drive the new relay protection principle and application of new technology and new change, become a new subject in front of the researchers of relay protection.
Operating principle of magnetic latching relay:
Solid State Relay An automatic circuit control device that causes a predetermined step change in the controlled electric quantity in the output circuit when the change of the excitation quantity in the input circuit reaches a specified value. It has an induction mechanism that can reflect a certain amount of external excitation (electric or non-electric), an executive mechanism that can control the "on" and "off" of the controlled circuit, and an intermediate comparison mechanism that can compare, judge and convert the amount of excitation. Relays are widely used in the fields of automatic control, remote control and telemetry, communication, broadcasting and aerospace technology, etc. They play the role of controlling, protecting, regulating and transmitting information.  
Main technical indicators of magnetic latching relay:
1, coil power supply voltage: 0-50V, resolution 0.01V, error 1%±0.05V
2, coil power supply current: < 1000mA
3, slow test test time:
4, quick test test time:

Measuring range resolution accuracy

1. Temperature: 2-51 DHS C 0.02 DHS in C + + / - 0.1 1% DHS C
2. Coil resistance: 10-500 Ω Ω 0.2 + / - 1% + / - 0.2 Ω
3. The contact resistance: 10 a/V 13.5:0-500 - m Ω Ω 0.2 m plus or minus 1% + / - 0.5 m Ω
1 a / 6 v: 0-500 - m Ω Ω 0.2 m plus or minus 1% + / - 0.5 m Ω
1 a / 6 v: 0-500 - m Ω Ω 0.2 m plus or minus 1% + / - 0.5 m Ω
4. Pulling voltage: 0-50V 0.02V ±1%±0.02V
6. Restore voltage: 0-50V 0.02V ±1%±0.02V
7. Suction time: 0-65ms 0.01ms ±0.1ms
0-65ms 0.01ms ±0.1ms
9. Release time: 0-65ms 0.01ms ±0.1ms
0-65ms 0.01ms ±0.1ms