overcurrent protection
Time:2021-09-07
Views:499
The overcurrent protector is a device used for current overload protection. When it enters the setting state, the relay in the protection will automatically release, and the protector exits the protection state, effectively preventing the misoperation of the motor in the setting state. It can be widely used in the protection and monitoring of industrial three-phase motors and other electrical appliances in the machinery, metallurgy, building materials, chemical, textile, and other industries.
technical parameter
Rated current: 3amp — 25amp.
Rated voltage: 125/250vac 50vdc 50-60hz.
Breaking capacity: 1,000amp×125vac 20amp×205vac.
Insulation withstand voltage test: 1,500vac /min.
Reset switch overload: 10 times the current.
Minimum voltage: less than 0.25v.
Response time: within 60 seconds.
Insulation resistance: greater than 500vdc×100mΩ.
Line terminal temperature: 100% test at 25℃, the temperature rise is less than 25℃.
Contact life test: 125vac × 150% current test more than 500 times.
Protection method
1. Compound type: Integrate multiple protections together.
2. Limited power type: limit the total output power.
3. Rewinding type: the initial current is constant, the voltage drops to a certain value and the current starts to decrease.
4. Isolation type: After overcurrent, the current and voltage drop to 0, and then start to rise again and again.
5. Constant flow: The current is constant and the voltage drops.
Performance characteristics
1. High-speed short-circuit protection, the action time is less than 40ns, and there is no spark eruption at the short-circuit. (Effectively contain electrical fires)
2. High-speed and accurate lightning protection and overvoltage protection, the action time is less than 40ns, the overvoltage voltage is determined to be higher than 260v, and the lightning voltage is determined to be higher than 630v, and the digital processing is fast and accurate.
3. It has time-delay characteristics, high-precision over-current protection, and the accuracy reaches 0.1a.
4. Ultra-high-speed leakage protection, magical electric shock without feeling function.
5. Automatic reset for fault removal, each time a fault occurs, the built-in mcu will make accurate judgments. Once the fault is determined to be removed, it will automatically reset immediately without manual re-closing, which is truly maintenance-free. (For some products, it is quite unsafe to use a delay to force reset)
Protective function
● Overload protection
● Underload protection
● Locked-rotor protection
● Blocking protection
● Temperature protection
● Phase sequence protection
● Undervoltage protection
● Overvoltage protection
● Starting overtime protection
● Phase failure protection
● Unbalance protection
Setup steps
The setting steps of the over-current protector take jl-200 over-current protector as an example, and the specific operations are as follows:
1. After the jl-200 overcurrent protector (overcurrent protector) is powered on, the digital window of the jl-200 overcurrent protector (overcurrent protector) displays 000.
2. Long press the jl-200 overcurrent protector (overcurrent protector)【setting】key for 5 seconds to enter the setting mode (the motor is in a static state, when the current is 0, it can enter the setting state; when the motor is running, the current is not 0 , Can not enter the setting state, but can query the setting content). At the same time [Settings] [Overload] characters are lit, enter the current setting, press the [△] [▽] key to set the current value, long press [△] to send continuously, press [△] to enter one digit, press [▽] One drop by one. After setting the current value, press the [Set] key to save the setting value and skip to the next setting item.
3. [Settings] [Blocking] characters are lit, set the motor blocking time allowed (at the same time the action curve is also set), according to the action characteristics of the motor, press the [△] [▽] key to select the corresponding action curve ( 3, 6, 9, 12, 15). After selecting the action curve, press the [Set] key to save the setting value and skip to the next setting item.
4. [Settings] [Underload] characters are lit, set the motor underload current percentage, press the [△] [▽] key to set the corresponding underload current and rated current percentage. Press【Setup】key to save the setting value and skip to the next setting item.
5. [Settings] [Phase Sequence] characters are lit to set whether the motor phase sequence protection function is on (on) or off (off). Press【Setup】key to save the setting value and skip to the next setting item.
6. [Settings] [Overvoltage] characters are lit, press [△] [▽] key to set the overvoltage value, press [Settings] key to save the setting value, and skip to the next setting item.
7. [Settings] [Undervoltage] characters are lit, press the [△] [▽] key to set the undervoltage value, press the [Settings] key to save the setting value, and skip to the next setting item.
8. Only the 【Settings】character is lit, enter the "Reset Mode" selection, press the【△】【▽】key, select【au】(automatic reset),【hu】(manual reset)
9. Press the【Setup】key to save the setting value and skip to the next setting item. Display [Settings] The digital window displays end, indicating that the jl-200 overcurrent protector (overcurrent protector) has been set.
10. Press [Set] to save the settings and exit the jl-200 overcurrent protector (overcurrent protector) setting state.
Scope of use
The overcurrent protector is used in multi-function protection occasions such as computer sockets, combination sockets, power converters, instrumentation, motor multi-function power strips, small generators and so on.
