How to use and principle of current limiter

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How to use and principle of current limiter

Posted Date: 2024-02-07

What are the methods of using current limiter?

There are many ways to use a current limiter, and the specific method of use depends on the application scenario and needs. Here are some common ways to use current limiters:

1. Electronic equipment protection: Current limiters are commonly used in electronic equipment to protect electronic components, circuits and power supplies. For example, adding a current limiter to a circuit can prevent excessive current from damaging components or causing a fire. The current limiter can be used at the power supply end or at a specific circuit location. Select the appropriate current limiter type and current rating according to your needs.

2. Power management: Current limiters can also be used in power management to stabilize power output and protect power equipment. For example, use a fuse current limiter on the power input to prevent overcurrent from damaging the power supply device or system.

3. Charger protection: Current limiters can be used to control the output current of charging equipment. The use of current limiting devices in chargers for mobile phones, tablets, electric vehicles, etc. can control the charging current to prevent overcurrent from damaging the charging equipment or rechargeable batteries.

4. Optical fiber communication: In optical fiber communication systems, photoelectric current limiters can be used to control the power and current of optical signals to avoid fiber damage or overloading of optoelectronic components.

5. Component protection: Current limiters can protect linear components (such as resistors, capacitors, etc.) and semiconductor devices (such as diodes, transistors, etc.) from overcurrent damage. By selecting an appropriate current limiter and connecting it in series with the component that needs to be protected, the flow of overcurrent can be limited.

The principle of current limiting:

When the voltage u1 flowing through the resistor r1 is greater than the power supply voltage uc; an electromotive force e2 is generated on r2, and the magnitude of this electromotive force is proportional to the voltage v on r2.

1. Capacitor c.

2. Inductor l3 and capacitor c4, and their resistance values ​​are r1, v, c1 and c2 respectively.

Then two induced electromotive forces will appear at both ends of resistor r2: e2-=e1+-e2; voltage drop u1=+u2=-ui;

In the case of two power supplies and two loads in the loop: e1-=ei+ie; e2-=ei-(ie); Since two reverse-biased high-order harmonic components appear in the loop, Therefore, a larger amplitude ripple will appear at the output end. In order to reduce the amplitude change of the output end to adapt to the requirements of the power grid, the input side must be filtered. Therefore, filter circuits were created.

In order to improve the anti-interference ability and reliability of the system and extend the service life of the equipment, some measures must be taken to improve the anti-interference ability and reliability of the system.

How to make the current limiter not limit the current?

If you want the current limiter to not limit the current, you can consider the following methods:

1. Replace current limiter: Select a current limiter with a higher current rating to replace the current limiter currently in use. A higher current rating will allow more current to pass so that current limiting does not occur.

2. Bypass the current limiter: The current can be bypassed by rewiring or adjusting the circuit connections. Please note that before bypassing a current limiter, you need to fully understand the function and design purpose of the current limiter to ensure that the bypass will not cause damage or overload the circuit or equipment.

3. Adjust the current limiter parameters: Some current limiters have adjustable parameters. For example, the current limiting parameters can be changed through knobs, switches or other adjustment devices. Check the specifications and instructions of the flow restrictor to learn how to adjust the parameters of the flow restrictor and follow the instructions to make the correct adjustment.

4. Check the circuit load: The current limit of the current limiter is based on the circuit load. If the circuit load exceeds the current limiter's rated range, the current limiter will begin to limit the current. To prevent the current limiter from limiting current, you can check whether the circuit load is appropriate and reduce the load as necessary to make it within the working range of the current limiter.

5. Check the power supply: The output voltage and current of the power supply may also affect the operation of the current limiter. Ensure that the output of the power supply is stable and meets the requirements of the current limiter to ensure that the current limiter works normally without limiting current.

Review Editor: Huang Fei

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