Hall sensor principle, detection method and use - Solutions - Huaqiang Electronic Network

Probe current voltage pin 420*4450 head diameter 5.0 over current current and voltage pin

Photocoupler

Principle of Hall Sensor The magnetic flux generated by the primary current Ip is concentrated in the magnetic circuit, and the Hall device detects the Hall voltage signal, which is amplified by an amplifier, and the voltage signal accurately reflects the primary current.
The magnetic flux generated by the primary side current Ip of the magnetic balance Hall current sensor is balanced with the magnetic flux generated by the secondary side coil generated by the amplification of the Hall side by the secondary side coil. The secondary current Is accurately reflects the primary current.
The magnetic balance Hall current transmitter and the voltage transmitter primary voltage Vp are converted into the primary current Ip by the primary side resistor R1, and the magnetic flux generated by Ip and the secondary side current Is generated by the amplification of the Hall voltage are passed through the secondary side coil. The resulting magnetic flux is balanced. The secondary current Is accurately reflects the primary voltage. Current sensor detection method A current sensor is an electrical component that detects the current of the power line. The output signal is sent to other execution circuits according to different needs, and further displays the current value and controls other electrical appliances.
Two current sensor main characteristic parameters
1. Standard rating and rated output current The standard rating is related to the model of the sensor product. Current sensor rated output current, generally 10~400mA.
2. The offset current offset current is also called residual current or residual current. It is mainly caused by the unstable operation state of the operational amplifier in the Hall element or electronic circuit.
3. The linearity linearity determines the degree to which the sensor output signal (secondary current IS) is proportional to the input signal (primary current IP) within the measurement range.
4, temperature drift
5. The overload capability of the overload current sensor means that when the current overload occurs, the primary current will increase outside the measurement range, and the duration of the overload current may be short, and the overload value may exceed the allowable value of the sensor. Current value sensors are generally not measured, but do not cause damage to the sensor.
6. The accuracy of the precision current sensor depends on the standard rated current. The effects of offset current, linearity, and temperature drift must also be considered when assessing sensor accuracy.
If you are a user, pay attention to the specifications and models.
The use of current sensors and voltage sensors requires measurement and control of current and voltage in many applications in scientific experiments and industrial applications, especially in some cases where high current and high voltage measurements and control are required, as well as current and voltage requirements. In the case of high accuracy, it is necessary to use a current-voltage sensor that is safe, convenient, reliable, and highly accurate. In the early days, shunts and voltage dividers were used to detect current and voltage. However, this method cannot measure the main circuit in isolation. This method is unsafe and has low accuracy. Later, people invented the transformer. Compared with the method of direct shunting and voltage division, it realizes the isolation detection of the main loop, which is undoubtedly a big progress, but its application range is narrow, only suitable for 50Hz sine wave work. Frequency detection, it can't do anything for other waveform current and voltage measurements.
With the development of power electronics technology, the original current detecting components (such as shunts, transformers) can not meet the medium, high frequency, high di / dt, wide spectrum current waveform transmission, Hall current voltage sensor is to make up for this A vacant, main detection component with a wide range of applications and prospects. Compared with common transformers, Hall current and voltage sensors have the following characteristics:
1. Wide measurement range: It can measure the current and voltage of arbitrary waveforms, such as DC, AC, pulse, triangle waveform, etc., and even faithfully reflect transient peak current and voltage signals;
2. Fast response: The fastest response time is only 1us.
3. High measurement accuracy: its measurement accuracy is better than 1%, which is suitable for the measurement of any waveform. The common transformer is an inductive component that affects the waveform of the signal under test after being connected. Its general accuracy is 3%~5%, and it is only suitable for 50Hz sinusoidal waveform.
4. Good linearity: better than 0.2%
5. Good dynamic performance: fast response time, less than 1us; common transformer response time is 10~20ms.
6. Working frequency bandwidth: Signals in the frequency range of 0~100KHz can be measured.
7. High reliability, long mean time between failures: mean time between failures > 5 10 hours
8. Strong overload capability and large measuring range: 0---tens of amps to tens of amps
9. Small size, light weight and easy to install.
Due to the advantages of Hall current and voltage sensors, it can be widely used with variable frequency speed control devices, inverter devices, UPS power supplies, inverter welding machines, electrolytic plating, CNC machine tools, microcomputer monitoring systems, power grid monitoring systems, and isolation detection currents. In various fields of voltage.