Product Description:

An air Circuit Breaker (ACB) is an electrical device used to provide Overcurrent and short-circuit protection for electric circuits over 800 Amps to 10K Amps. These are usually used in low voltage applications below 450V. 

Leidun Electric’s LDW9 series intelligent air-operated circuit breaker is suitable for the distribution network of AC, 50Hz/60HZ, rated working voltage up to 690V, rated current 400A-6300A , used to distribute electric energy and protect lines and power equipment from damaged by faults such as overload, overcurrent, undervoltage, short circuit, single-phase grounding, etc. The air circuit breaker has an intelligent high-precision selective protection function which improves the reliability of power supply. It also has a standard RS485 communication interface which can carry out four kinds of remote functions to meet the requirements of cluster control center and automation system.

Four remote fucnctions includes remote measurement, remote communication, remote control, and remote adjustment. This series of air circuit breakers have the characteristics of compact structure, high breaking capacity, and no arcing distance. The ACB air circuit breaker can be used as an isolation switch or disconnector without an intelligent slunt trip unit and a sensor. The ACB complies with GB14048.2  (for Low-voltage Switchgear And Control Equipment Low-voltage Circuit Breaker) and IEC60947-2 (for Low-voltage Switchgear And Control Equipment Circuit Breaker” and other standards.

 ** Products can be customized to suit your needs.**

Normal Working Conditions:

Ambient air temperature: The upper limit should not exceed +40℃, the lower limit should not be lower than -5℃. The average value of 24h should not exceed +35℃.

Atmospheric conditions: The relative humidity of the atmosphere does not exceed 50% when the ambient air temperature is +40℃. There can be higher relative humidity at lower humidity. The monthly average highest relative humidity of a wet month is 90% while the monthly average lowest temperature is +25℃. the condensation on the surface of the product due to temperature changes must be taken into account.

Installation location: The altitude does not exceed 2000m, and the vertical inclination of the circuit breaker does not exceed 5°. Air circuit breakers with rated working voltage of 690V and below, undervoltage release, and power transformer primary coil are used for installation category IV.

Installation category for auxiliary circuit and control circuit : III

 

Brief Introduction of Air Circuit Breaker Structure:

The fixed air circuit breaker is mainly composed of a contact system, an intelligent controller, a manual operating mechanism, an electric operating mechanism, and a mounting plate.

The drawer type circuit breaker is mainly composed of a contact system, an intelligent controller, a manual operating mechanism, an electric operating mechanism, and a drawer seat.

The air circuit breaker has the characteristics of compact structure and small volume. The contact system is enclosed in the insulating bottom plate, and each phase contact forms a small chamber. The intelligent controller, manual operating mechanism, and electric operating mechanism are arranged in front of them to form independent units, which is convenient for maintenance and repair.

The drawer type circuit breaker is composed of a plug-in circuit breaker and a drawer base, and the plug-in circuit breaker is placed in and out of the guide rail in the drawer base. The drawer type circuit breaker has three working positions: Connected, Tested and Detached positions. The position change is realized by the rotation of the hand scale. And the indication of the three positions is displayed by the pointer on the crossbeam of the drawer base.

When in the “connected” position, both the main circuit and the secondary circuit are connected. When in the “test” position, the main circuit is disconnected and separated by an insulating partition and only the secondary circuit is connected. Some necessary action tests can be carried out. When in the “separated” position, the main circuit and the secondary circuit are all disconnected.

The drawer type air circuit breaker has a mechanical interlocking device. The circuit breaker can only be closed in the connection position and the connection position, and the circuit breaker cannot be closed in the middle position between the connection and the test.

 

Intelligent Release Performance:

Intelligent releases are divided into: L type (economical type), M type (standard type), H type (communication type);

It has four-stage protection features: overcurrent long delay inverse time limit, short circuit short delay inverse time limit (and definite time limit), short circuit instantaneous protection, and asymmetric grounding (zero connection) fault protection.

Among them, the L-type short-circuit short-time delay definite time protection and asymmetric grounding (zero connection) fault protection are optional functions.

Setting function: adopt coding switch and code switch setting (L type) or digital display and key setting (M, H type). Users can set various protection parameters according to their needs to form the required protection characteristics.

Display function: display the working current of the circuit breaker and display various protection states.

Self-checking function: self-diagnosis of overheating of ambient temperature, self-checking of CPU, ROM, RAM and I2C communication within the microcontroller.

Fault memory function: memorize the fault current, delayed action time, and fault category when tripping caused by a line fault.

Thermal memory function: memory overload and short circuit caused by the heating degree of the circuit or equipment (reset after power off).

Optional functions: voltmeter function, load monitoring function, various overload alarm signal output functions, MCR on-off and analog trip protection functions.

In addition to all the functions of the M type, the H-type intelligent trip unit also has a serial communication interface. Through the communication interface, a master-slave LAN system can be formed, with 1-2 computers as the master station, several intelligent circuit breakers or other communications The interface element is used as a slave station, and for the circuit breaker unit, the system can realize the remote “four remote control” function.

 

Series LDW9 – Fixed Air-operated Circuit Breaker (ACB)  Series
Image	Model No.	Rated Current	Unit	QTY/CTN
	LDW9-2000/3P	630A	SET	1
	LDW9-2000/3P	800A	SET	1
	LDW9-2000/3P	1000A	SET	1
	LDW9-2000/3P	1250A	SET	1
	LDW9-2000/3P	1600A	SET	1
	LDW9-2000/3P	2000A	SET	1
	LDW9-3200/3P	2000A	SET	1
	LDW9-3200/3P	2500A	SET	1
	LDW9-3200/3P	3200A	SET	1
	LDW9-3200/3P	4000A	SET	1
	LDW9-6300/3P	4000A	SET	1
	LDW9-6300/3P	5000A	SET	1
	LDW9-6300/3P	6300A	SET	1
	LDW9-2000/4P	630A	SET	1
	LDW9-2000/4P	800A	SET	1
	LDW9-2000/4P	1000A	SET	1
	LDW9-2000/4P	1250A	SET	1
	LDW9-2000/4P	1600A	SET	1
	LDW9-2000/4P	2000A	SET	1
	LDW9-3200/4P	2000A	SET	1
	LDW9-3200/4P	2500A	SET	1
	LDW9-3200/4P	3200A	SET	1
	LDW9-6300/4P	4000A	SET	1
	LDW9-6300/4P	5000A	SET	1
Series LDW9 – Three-pole Drawer Type Air-operated Circuit Breaker (ACB)  Series
Image	Model No.	Rated Current	Unit	QTY/CTN
	LDW9-2000/3P	630A	SET	1
	LDW9-2000/3P	800A	SET	1
	LDW9-2000/3P	1000A	SET	1
	LDW9-2000/3P	1250A	SET	1
	LDW9-2000/3P	1600A	SET	1
	LDW9-2000/3P	2000A	SET	1
	LDW9-3200/3P	2000A	SET	1
	LDW9-3200/3P	2500A	SET	1
	LDW9-3200/3P	3200A	SET	1
	LDW9-3200/3P	4000A	SET	1
	LDW9-6300/3P	4000A	SET	1
	LDW9-6300/3P	5000A	SET	1
	LDW9-6300/3P	6300A	SET	1
Series – LDW9 Four-pole Withdrawable Air-operated Circuit Breaker (ACB)
Image	Model No.	Rated Current	Unit	QTY/CTN
	LDW9-2000/4P	630A	SET	1
	LDW9-2000/4P	800A	SET	1
	LDW9-2000/4P	1000A	SET	1
	LDW9-2000/4P	1250A	SET	1
	LDW9-2000/4P	1600A	SET	1
	LDW9-2000/4P	2000A	SET	1
	LDW9-3200/4P	2000A	SET	1
	LDW9-3200/4P	2500A	SET	1
	LDW9-3200/4P	3200A	SET	1
	LDW9-6300/4P	4000A	SET	1
	LDW9-6300/4P	5000A	SET	1
Products can be customized to suit your needs.
Accesorries for Air-operated Circuit Breaker (ACB)
Image	Description	Unit
	Phase Partition	SET
	Auxiliary switch (6-open and 6-close)	PC
	Shunt Trip	PC
	Undervoltage Release  (Auxiliary Suction)	PC
	Undervoltage Release   (Automatic Suction)	PC
	Time Delay Undervoltage Release	PC
	Closed Electromagnet	PC
	Electromotor	PC
	One Lock with One Key	PC
	Two Locks with One Key	PC
	Three Locks with Two Keys	SET
	Mechanical Interlock (Soft)	SET
	Mechanical Interlock (Hard)	SET
	Intelligent Controller 630-2000A	SET
	Intelligent Controller 2500-4000A	SET
	H-Shaped Smart Shunt Trip	PC
	DC Smart Shunt Trip (Module)	SET
	Vertical In-and-Out Bus Unit 630-1600A	SET
	Vertical In-and-Out Bus Unit 2000A	PC
	Voltage Display Unit	PC
	Load Monitoring Unit	PC
	Dual Power Supply Automatic Conversion Controller	PC
	3P+N  Earth Current Type (W-shaped)	PC
	Leakage CurrentTransformer	PC