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What Are The Protection Devices For Low Voltage Switchgear?

Jul. 13, 2019

The rated current of the Low Voltage Switchgear is AC 50Hz, rated power 380v power distribution system for power, lighting and distribution of electrical energy conversion and control. The product has strong breaking ability, good dynamic thermal stability, flexible electrical scheme, convenient combination, series, practicality and novel structure.


Low Voltage Switchgear

Low Voltage Switchgear


So what are the low voltage switchgear protection devices?

(1) Overload protection: thermal relays, thermal trips, fuses (lighting and non-impact load lines or equipment).

(2) Short circuit protection: fuse, electromagnetic overcurrent relay, trip unit.

(3) Undervoltage and voltage loss protection: undervoltage and voltage loss release.

(4) The rated current of the fuse should be greater than 1.2 to 2.5 times the long-term allowable load of the motor.

(5) Bimetal thermal relay is suitable for cage motors with long-term operation and constant load. It is not suitable for other types of motors. The current setting of thermal relays should be selected according to the rated current of AC motors (1.1~1.2Ie).

(6) When the automatic air switch is selected, its single-phase short-circuit current should be greater than 1.5 times the instantaneous (or short delay) action overcurrent release setting value.


We sell Reliable Low Voltage Switchgear, if you need, you can contact us.

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