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Low Voltage Switch Can Control The Operation And Stop Of Low-voltage Electrical Equipment
Sep 26, 2017

1, low-voltage switch selection points

General low voltage switch selection

(1) the rated current of the release is not less than the calculated current of the line.

(2) low voltage switch rated voltage is not less than the rated voltage of the line.

2, low-voltage switch protection characteristics of knowledge

Low-voltage switch is generally self-contained long delay protection and short-circuit instantaneous protection, molded case switch protection settings at the factory has been set at the time of purchase should be based on load characteristics to choose the appropriate set value of the switch.

Low-voltage switch with intelligent release of the universal switch set value through the intelligent panel or external protection generally use over-current protection and time-limited protection, before the need to calculate the set value and set the value of the calibration.

(3) The rated voltage of the undervoltage release is equal to the rated voltage of the line.

(4) low-voltage switch rated current is not less than the calculated load current of the line.

(5) low-voltage switch limit breaking capacity is not less than the line in the largest short-circuit current.

(6) single-phase short-circuit current at the end of the line ÷ low-voltage switch instantaneous (or short delay) trip setting current ≥1.25

3, the use of low-voltage switch

Low-voltage switch is when the car to the car power supply voltage is less than the number of car power will automatically shut down. Is a commonly used electrical components, car power supply of this feature is a protective function to protect the car's power supply equipment is not damaged, give priority to ensure that the car itself is normal, such as to ensure that the car can be normal ignition. One low-voltage switchgear is the use of low-voltage switch to design, suitable for power plants, petroleum, chemical, metallurgy, textile, high-rise buildings and other industries, as transmission, distribution and power conversion purposes.


Reasonable design: According to the fugitive, picture and other characteristics of a variety of switching electrical design of the unit, the combination of functional units.

Structure of the general, flexible assembly: C-type profiles to meet a variety of structural forms. I care level and the use of surrounding conditions.

The quasi-module can be composed of protection, operation, conversion, control and other standard unit module structure arbitrarily selected group of revolution.

Security protection: the use of isolation between the region and the functional unit into the line and outlet of the isolation, effectively enhance the security performance.

Technical parameters: the main technical parameters in the international leading level.

4, what is the low-voltage switch?

Can control the operation and stop of low-voltage electrical equipment, also includes lighting equipment circuit (light bulb) equipment on and off the device called low-voltage switch. Low-voltage switch is the name suggests is to control low-voltage electrical equipment on the switch. Such as: control 380V motor start and stop the air switch, control the lighting circuit through and off the 3P, 2P, 1P air switch. Low-voltage switchgear inside the control switch are low-voltage switch category.

5, the choice of low-voltage switch

The rated voltage of the closed load switch shall not be less than the rated voltage of the working circuit; the rated current shall be equal to or slightly larger than the operating current of the circuit.

Used to control the motor work, taking into account the motor starting current is large, should make the switch rated current not less than 3 times the rated current of the motor.

6, low-voltage switch to promote urban and rural integration

From the market situation, China's production of low-grade low-voltage switch is basically occupied the vast majority of the domestic market, but the domestic high-end low-voltage switch in addition to individual products with foreign similar products evenly divided, the other domestic high-end low-voltage switch domestic market share is still very low. Therefore, the domestic low-voltage switch companies must increase research and research and development of new products, increase the basis of common technology research, but the development of new products should not be behind closed doors, but should be based on the actual market demand, based on user needs for enterprise users Out of their actual needs of the product, which can be invincible.

With the smart grid into the important stage of comprehensive construction and further promote the construction of urbanization in China, urban and rural distribution network of intelligent construction will be fully opened, smart grid and intelligent complete sets of equipment, intelligent distribution, control system will usher in the development of gold Period, which on the domestic low-voltage switch products made intelligent development requirements. For the domestic low-voltage switch market, this is undoubtedly a huge opportunity, but also a severe test.