What are the precautions for using Hall sensors?
The Hall current sensor is based on the magnetic balance Hall principle, which is the closed-loop principle. When the magnetic flux generated by the primary current IP is concentrated in the magnetic circuit through a high-quality magnetic core, the Hall element is fixed in the air gap to detect the magnetic flux. The reverse compensation current is output through a multi turn coil wound around the magnetic core to cancel out the magnetic flux generated by the primary current IP, so that the magnetic flux in the magnetic circuit always remains zero. After special circuit processing, the output terminal of the sensor can accurately reflect the current changes of the primary current. Today, Wei Kewei will talk about the precautions when using Hall current sensors, hoping that everyone can take a good look at the following content.
(Single phase DC high current sensor-B13
1. How to choose
A. When selecting a current sensor, attention should be paid to whether the perforation size can ensure that the wire can pass through the sensor;
B. When choosing a current sensor, attention should be paid to whether there are special environments such as high temperature, low temperature, high humidity, and strong earthquake in the application environment on site;
C. When choosing a current sensor, attention should be paid to whether the spatial structure meets the requirements;
2 Instructions for use
58彩票A. When wiring, pay attention to the exposed conductive parts of the wiring terminals to prevent ESD impact as much as possible. Only engineers with professional construction experience can perform wiring operations on this product. The connecting wires of the power supply, input, and output must be connected correctly and cannot be misplaced or reversed, otherwise it may cause product damage.
58彩票B. The installation and use environment of the product should be free of conductive dust and corrosive Egypt
C. Severe vibration or high temperature may also cause product damage, and attention must be paid to the usage environment.
3 Precautions for using current and voltage sensors
(1) Current sensors must be selected with different specifications based on the rated effective value of the measured current. If the measured current exceeds the limit for a long time, it will damage the terminal power amplifier tube (referring to magnetic compensation type). Generally, the duration of twice the overload current should not exceed 1 minute.
58彩票(2) The voltage sensor must be connected in series with a current limiting resistor R1 on the primary side according to the product instructions to obtain the rated current on the primary side. In general, the duration of double overvoltage should not exceed 1 minute.
(3) The optimal accuracy of current and voltage sensors is obtained under the condition of primary rated value, so when the measured current is higher than the rated value of the current sensor, the corresponding larger sensor should be selected; When the measured voltage is higher than the rated value of the voltage sensor, the current limiting resistor should be readjusted. When the measured current is less than 1/2 of the rated value, in order to obtain the best accuracy, the method of multiple turns can be used.
58彩票(4) Sensors with insulation withstand voltage of 3KV can work normally for a long time in AC systems of 1KV and below and DC systems of 1.5KV and below. Sensors with insulation withstand voltage of 6KV can work normally for a long time in AC systems of 2KV and below and DC systems of 2.5KV and below. Be careful not to use them under overvoltage.
(5) When used on devices that require good dynamic characteristics, it is best to use a single copper aluminum busbar that matches the aperture, as replacing small or multiple turns can affect the dynamic characteristics.
58彩票(6) When used in high current DC systems, if the working power supply opens or malfunctions for some reason, the iron core will produce significant residual magnetism, which is worth noting. Residual magnetism affects accuracy. The method of demagnetization is to not add a working power supply, and to apply an alternating current to the primary side and gradually reduce its value.
58彩票(7) The sensor's ability to resist external magnetic fields is: when the distance from the sensor is 5-10cm and the current exceeds twice the value of the sensor's primary current, the generated magnetic field interference can be resisted. When wiring three-phase high current, the phase to phase distance should be greater than 5-10cm.
58彩票(8) In order to ensure that the sensor operates in the best measurement state, a simple typical voltage regulator power supply as shown in Figure 1-10 should be used.
(9) The magnetic saturation point and circuit saturation point of the sensor give it strong overload capacity, but the overload capacity is time limited. When testing the overload capacity, the overload current of more than twice should not exceed 1 minute.
(10) The temperature of the primary current busbar shall not exceed 85 ℃, which is determined by the characteristics of ABS engineering plastic. If users have special requirements, high-temperature plastic can be selected as the shell.
58彩票In summary, Wei Kewei has explained the precautions when using Hall current sensors, and we believe that everyone's understanding of Hall current sensors will become more and more profound. If you have a need for Hall sensors or have any further questions about Hall sensors, you can directly contact customer service or leave a message below.
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