第2页_FAQ_SENCORUI (Shenzhen) Intelligent Electrical Co., Ltd.

Q What are the characteristics of Hall current sensors?: A

Hall current sensors have a variety of characteristics, including:
1. High accuracy: The accuracy of Hall current sensors in the working area is usually better than 1%, which is suitable for measuring various waveforms.
2. Good linearity: The linearity is better than 0.5%, which can ensure the accuracy of the measurement results.
3. Good dynamic performance: The dynamic response time is less than 7 microseconds, the tracking speed is high, and it is suitable for measuring rapidly changing currents.
4. Strong overload capacity: The measurement range is large and can withstand large overload currents without damage.
5. Non-contact measurement: The Hall current sensor senses the current by measuring the magnetic field, without direct contact with the circuit being measured, so it has the advantage of isolated measurement.

Q What is the working principle of Hall current sensor?: A
The working principle of the Hall current sensor is based on the Hall effect. When current passes through a conductor, a magnetic field is generated around the conductor. The Hall element is a semiconductor material. When a magnetic field acts on the Hall element, a potential difference is generated on both sides of the element. This potential difference is called the Hall voltage. The magnitude of the Hall voltage is proportional to the product of the control current and the magnetic induction intensity. Therefore, by measuring the magnitude of the Hall voltage, the current of the current-carrying conductor can be indirectly measured.

Q How to deal with the broken casing of transformer?: A
When the transformer shell is broken, the transformer should be shut down immediately and the maintenance personnel should be notified to handle it. The shell crack may cause the transformer to be damp inside, insulation damage and other faults.

Q What should be done if there is spark discharge between the transformer leads and the casing?: A
When spark discharge is found between the transformer lead and the shell, the transformer should be stopped immediately and the insulation of the lead and shell should be checked. If the insulation is damaged, it should be replaced or repaired in time.

Q How should you deal with faults such as severe discharge sound, heat, smoke, or burning smell in the transformer?: A
When these faults occur, the transformer should be stopped immediately and the maintenance personnel should be notified to handle them. These faults may be caused by insulation damage inside the transformer, winding short circuit, etc.

Q Why is it not allowed to replace the primary fuse of the voltage transformer with an ordinary fuse after it blows?: A
Taking a 10kV voltage transformer as an example, the rated current of the primary fuse is 0.5A. The fuse filled with quartz sand has good arc extinguishing performance and large current breaking capacity, and also has the function of limiting short-circuit current.

Q Why should the secondary winding of the transformer be grounded?: A
The purpose of grounding the secondary winding of the transformer is to reduce the ground potential of the secondary system when the primary and secondary windings are broken down. The smaller the grounding resistance, the lower the low potential, thus ensuring personal safety. In addition, grounding can also prevent the high potential caused by the damage of the primary and secondary insulation from causing harm to equipment and personnel.