Kyungdong Electric

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Kyungdong Electric

Kyungdong Electric

Air Circuit Breaker




Transaction Process

Please contact the manufacturer/supplier.


Contact the manufacturer/supplier.


Contact the manufacturer/supplier.


Contact the manufacturer/supplier.


The Republic of Korea


<tab title="ACB (Fixed Type. Draw out Type)">

■ Names of exterior part

Kyungdong Electric Air Circuit Breaker KD05 Series

① Front cover

② Arc extinguish chamber

③ Control circuit terminal

④ Electronic trip relay

⑤ Counte

⑥ Closing button

⑦ Charging handle

⑧ Name plate

⑨ Caution mark

⑩ position indicator

⑪ Pushing/Drawing lever hole

⑫ Charging indicator

⑬ Extension rail

⑭ Trip button

⑮ ON/OFF indicator

(16) Draw-out profile

(17) Main body profile

(18) Handle

■ Internal Structure

Kyungdong Electric Air Circuit Breaker KD05 Series 1

① Front cover

② Electronic trip relay

③ Auxiliary switch

④ Arc extinguish chamber

⑤ Closing coil

⑥ ON/OFF indicator

⑦ Closing mechanism

⑧ Trip mechanism

⑨ Trip coil

⑩ Charging handle

⑪ Charging indicator

⑫ Draw-out mechanism

⑬ Position indicator

⑭ Gear block

⑮ Draw-out cam

(16) Extension rail

(17) Closing spring

(18) Movable shunt

(19) Safety shutter

(20) Circuit breaker connection conductor

(21) Load side conductor

(22) Draw-out conductor

(23) Breaking spring

(24) Power supply side conductor

(25) Fixed contact

(26) Traveling contact

(27) Draw-out main body

■ Specifications

ISO 9001, ISO14001, applied for patent

Compact and light weight

The product is designed to be efficient and suitable for stand-alone switchboards by reducing its size and weight up to 85% to that of existing products.

Less size variation

Size variations have been reduced from four types to three types.

630~1250A / 1600~2000A / 2500A / 3200~4000A → 630~1600A / 2000~2500A / 3200~4000A

Safe and convenient

The control circuit terminal block is attached on the upper side of the product.

The mechanism and attached devices have been modularized in order to provide easy maintenance and inspection.

The draw-out rail has been significantly improved to allow easy draw-out.

The arc space has been minimized. The modular type cover offers a better appearance.

High-function digital protective relay

It is easier to identify the trip status with the trip status LED on the digital protective relay.

- The OCR tester (sold separately) offers a high-accuracy current detection circuit.

Various attachments

Improved quality through the application of diverse attachments.

Close first, open later type

When closing and opening main contact, the contact on the N phase contacts before and falls later than R, S, T phases, and thus prevents accidents that may occur from the previous position (especially when using single-phase load).

Example of configuring ACB type

Kyungdong Electric Air Circuit Breaker KD05 Series 2

S : type breaking capacity / H : High type breakung capacity

Rated operating voltage(V)660660660660660660660660660
Frame current(AF)6308001000125016002000250032004000
Setting Base Current (A)6306308001000125016002000250032004000
Rated service short circuit (lcs)(kA)
Rated short circuit making capacity (Icm)(kA)
220 / 240V6075607565756075607560756075607585100
380 / 415V557055705570557055705570557055707590
440 / 500V506550655065506550655065506550656585
600 / 660V425542554255425542554255425542555575
Below 500V105143105143105143105143105143105143105143105143143187
short time withstand
capacity(kA) AC 500V 이하
peak (kA, peak)105143105143105143105143105143105143105143105`143143187
1 Sec5065506550655065506550655065658585100
3 Sec303030305050506585
Operation timeTotal breaking timeBelow 45msBelow 50ms
Rated closing timeBelow 65msBelow 80ms
Number of poles3P/4P3P/4P3P/4P3P/4P3P/4P3P/4P3P/4P3P/4P3P/4P
enduranceMechanicalWithout maintenance100001000010000100001000010000100001000010000
With maintenance200002000020000200002000020000200002000020000
electricalWithout maintenance25002500250025002000100010001000600
With maintenance500050005000500050003500350035001500
Motor operationWithout maintenance500050005000500050003500350035001500


Draw-out type, Closing coil, Trip coil, Counter, OCR, Aux-switch(2a2b)

Operating voltage, OCR trip signal


OCGR, CTD, Shutter device, OCR Tester, OCR alarm switch, Key switch,

Locationswitch, Auxiliary switch (AUX switch 3a3b,4a4b)

Product Attributes

ㆍDiversification is given to set circuit breaking conditions including electric current in a long time delay, in a short time delay, in an instantaneous trip and in ground fault. This provides a wide variety of choices and satisfaction of detailed needs.

ㆍThe energy for closing in store at springs, which brings about raped and precise operation.

ㆍEquipment can be used for either AC and DC according to the situation, which has diversified the choice as an option.

ㆍAll parts are standardized with molds to be repaired and maintained easily. And thorough inspection and standardized production bring about long durability.

ㆍReliability is much enhanced by the ability to confirm breaking by different causes.

Installation method

Fixed Type

The unit is directly connected to the panel board and is an economical method installation.

Draw out Type

It consists of two parts the main body of the breaker and the panel board frame.

It is directly connected to the panel board and the main body of the breaker is mounted on the draw out frame.

The main body of the breaker can be separated from the panel board without change in circuit.

Benefits easy checking for its function, easy repairing & charging part and maintenance, easy replacement of breaker itself.

Kyungdong Electric Air Circuit Breaker KD05 Series 3

Operation Method

Manual Storage Method

• It stores spring the energy needed for closing by moving the storage handle from up to down about 7 times.

• Repetition of the storage handle movement continues until the charging indicator displays "CHARGED".

※ Caution : Manual charging should be performed while the breaker is in opening state.

Automatic Storage Method

• It stores the energy needed for closing by using an electric storage motor , which is activated the closing circuit.

• When the breaker starts breaking, the motor is automatically activated to store the energy needed for closing.

• The storage motor is capable of storing energy 50 times. However, to do more than 50 times, it requires cooling for 10 minutes, as a minimum, preventing the motor from overheat.

Closing coil

• It is a Solenoid-State coil, which is operated by a closing signal coming from outside or by a pressing button attached to the front side.

Opening coil

• It is a Solenoid-State coil, which trips after receiving signals from OCR or from outside.

Kyungdong Electric Air Circuit Breaker KD05 Series 4

A TMS CHIP (Micro computer) adopted on the ACB Controller automatically displays three-phase voltage, current, frequency, power factor, and active and reactive power.

There is no need to open the panel door to control the ACB.

Economical Efficiency

ㆍThere is no need to install a separate CT as it is built inside the ACB.

ㆍNo wiring work is required as the standard operating line supplied between the ACB main body and controller connects both ends to the connector.

ㆍA voltmeter, ammeter, power meter, power factor meter, operating switch, and O.C.R relay are installed inside the ACB Controller, making it unnecessary to install additional instruments or wiring.

ㆍThe ACB Panel offers excellent cost-effectiveness for it is easy to build by simply installing the ACB, mounting the controller, and connecting the supplied cable to the connector.

Product Attributes

ㆍThe fuse attached on the 3-phase voltage cable of the voltmeter makes the product safe to use.

ㆍThe voltmeter automatically measures the 3-phase voltage cable supplied from the main body of the ACB from 220V~660V.

ㆍThe readout for each phase is displayed immediately by pressing a button.

ㆍACB Controller has a built-in O.C.R relay which allows the user to change and control the current settings in a safe and convenient manner.

ㆍThe indicator makes it easy to identify the cause of an ACB blockage cause by O.C.R.

ㆍProduct is equipped with a test terminal that can be used for testing the properties of O.C.R relay.

ㆍThere is an alert function that activates when the current being used exceeds 90% of the O.C.R setpoint.

ㆍThere is a built-in lock device which only the administrator can use to restrict operation of the product.

ㆍSpecifications, ACB main body dimensions, bus bar dimensions, and mounting hole dimensions are identical to those of the Standard ACB.

ㆍThe C•T ratio can be installed according to the customer’s request. C•T provided by our company are as below.
C•T capacity: 200/5A, 300/5A, 400/5A, 500/5A, 630/5A, 800/5A, 1000/5A, 1250/5A, 1600/5A, 2000/5A, 2500/5A, 3200/5A, 4000/5A, 5000/5A

ㆍ* To order a C•T capacity other than those stated, please state the details on the order form (Only applies to detachable type).

ACB Controller

Kyungdong Electric Air Circuit Breaker KD05 Series 5

① ACB closing button switch

② ACB breaking button switch

③ ACB breaking button switch

④ Ammeter

⑤ Voltmeter

⑥ Power factor, frequency meter

⑦ Wattmeter

⑧ Indicator LED Lamp

⑨ Operation status indicator-LED Lamp

⑩ O.C.R relay

Kyungdong Electric Air Circuit Breaker KD05 Series 6

① P,N 220 operating power terminal

② E earth terminal

③ PAT1,2 alert (alarm) contact draw-out terminal

④ Ammeter C.T connector

⑤ Voltmeter three-phase voltage connector

⑥ Operating circuit connector

⑦ Controller mounting bolt


CEO  Charlie ParkCorporate #  535-86-00664
Ace Dongbaek Tower 1-1101, 16-4, Dongbaekjungang-ro 16beon-gil, Giheung-gu, Yongin City, Gyeonggido, South Korea    (Post Code 17015)

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