OEM SJKM1 Moulded Case Circuit Breaker (MCCB) for Power Systems Supplier, Manufacturer

The SJKM1 Moulded Case Circuit Breaker (MCCB) is designed for AC 50/60Hz power systems up to 690V and 1250A. This SJKM1 MCCB provides reliable protection against overload, short circuit, and undervoltage in distribution networks. With models up to 400A frame size, it can also safeguard motors. Compliant with IEC 60947-2 and GB14048.2, the SJKM1 Moulded Case Circuit Breaker ensures safe power distribution and equipment protection. Its robust construction supports infrequent switching and motor starting, making it ideal for industrial and commercial applications. 

Product Description

Type Designation

SJKM1-Moulded-Case-Circuit-Breaker-(MCCB)-5
①Manufacturer Code
②Molded Case Circuit Breaker Code
③Design Code
④Frame Size
⑤Short-Circuit Breaking Capacity Level 4
⑥Operation method 3
⑦Number of Poles 2
⑧Trip Unit Method & File Code
⑨Function Code 1
⑩Type code(See Table 1 for N-pole of four-pole,no code for three-pole)

Notes:

1. There is no code for distribution circuit breakers; for motor - protection circuit breakers, use 2 to represent.

2. Number of poles: 2 for two - pole; 3 for three - pole; 4 for four - pole.

3. For handle - direct operation: use D to represent for power - distribution use, and use Z to represent for conversion - locking use.

4. For economy type: represent with E; for standard type: represent with M; for higher - reliability type: represent with H; for high - breaking type: represent with L.

Product Display

N - Pole Type Code

Type Code Description
Type ANo over - current release element is installed on the N - pole, and the N - pole is always connected, and does not close and open together with the other three poles.
Type BNo over - current release element is installed on the N - pole, and the N - pole closes and opens together with the other three poles (the N - pole closes first and opens later).
Type CAn over - current release element is installed on the N - pole, and the N - pole closes and opens together with the other three poles (the N - pole closes first and opens later).
Type DAn over - current release element is installed on the N - pole, and the N - pole is always connected, and does not close and open together with the other three poles.

Release Modes and Accessory Codes

Accessory Name Without Accessory Alarm Contact Shunt Release Auxiliary Contact Under - voltage Release Shunt Release Auxiliary Contact Two - group Auxiliary Contacts Shunt Release Under - voltage Release Auxiliary Contact Under - voltage Release
Release Mode Instantaneous Code 200 208 210 220 230 240 250 260 270
Compound Code 300 208 310 320 330 340 350 360 370
(Continued from the previous table)
Accessory Name Shunt Release Alarm Contact Auxiliary Contact Alarm Contact Under - voltage Release Alarm Contact Shunt Release Auxiliary Contact Alarm Contact Two - group Auxiliary Contact Alarm Contact Auxiliary Contact Under - voltage Release Alarm Contact
Release Mode Instantaneous Code 218 228 238 248 268 278
Compound Code 318 328 338 348 268 378

Notes:

1) 200 indicates the circuit breaker body with only an electromagnetic release; 300 indicates the circuit breaker body with thermal and electromagnetic releases.

2) For the two - level products SJKM1 - 125 and SJKM1 - 250, only 210, 310, 220, 320, 230, and 330 are available.

Normal Operating Conditions and Installation Conditions

Ambient temperature: The circuit breaker can operate normally at an ambient temperature range of -5°C to +40°C (except for special orders).
Altitude: The altitude of the installation site of the circuit breaker shall not exceed 2000m.
Pollution degree: The pollution degree of the circuit breaker is Grade 3.
Installation category: The installation category of the circuit breaker is Category III.
Installation position: The circuit breaker can be installed horizontally, vertically, or flat, without reducing its electrical performance.

Main Parameters and Technical Performances

Circuit Breaker Model SJKM1-63 SJKM1-125 SJKM1-250 SJKM1-400 SJKM1-630 SJKM1-800 SJKM1-1250
Pole Number 34 324 324 34 34 34 34
Rated Current In (A) 10 16 20 25 32 40 50 63 16 20 25 32 40 50 63 80 100 125 100 125 140 160 180 200 225 250 225 250 315 350 400 400 500 630 630 700 800 800 1000 1250
Rated Insulation Voltage Ui (V) 690 1000 1000 1000 1000 1000 1000
Rated Impulse Withstand Voltage Uimp (V) 6000 8000
Rated Working Voltage Ue (V) 400 AC400/690 AC400/690 AC400/690 AC400/690 AC400/690 AC400/690
Breaking Capacity Level LM LMH LMH LMH LMH H H
Ultimate Short-Circuit Breaking Capacity Icu (kA) (0-tCO) 400V 2550 355085 355085 5065100 5065100 100 100
690V 25 25 30 30 25
Service Short-Circuit Breaking Capacity Ics (kA) (0-tCOtCO) 400V 1830 253550 253565 355065 355065 65 50
690V 15 15 20 20 20

Appearance and Installation Dimensions

Appearance and installation dimensions of the fixed - type front - connected and rear - connected wiring
SJKM1-Moulded-Case-Circuit-Breaker-(MCCB) (1) SJKM1-Moulded-Case-Circuit-Breaker-(MCCB) (2)
Appearance and installation dimensions of fixed - type front and rear wiring
model Number Overall dimensions (mm) Mounting Dimensions (mm) Dimensions for Rear Terminal Wiring (mm)
LL1WHH1H2 abφd alb1d1H3H4
SJKM1-63L3135217688721925117425117185275
SJKM1-63M978228
SJKM1-634103
SJKM1-125L1505192866824301294.5301322265100
SJKM1-125M31048623
SJKM1-125H
SJKM1-125265---
412230
SJKM1-250L165641071088725351265.5351442470110
SJKM1-250M3165107124.510424.5
SJKM1-250H
SJKM1-250275--
4142
SJKM1-400325710514915010036.5441956.5442253270120
4198
SJKM1-630327011818215510841582007582344070120
4240
SJKM1-800328210221015810334.5702437702434870125
4280
SJKM1-12503406104210190140.558.57037510---
Handle H W Protrusion in the middle L W H
631713.56344225.5
125191312551235.5
2502212.525052234
40043.533.540089.5657
6304433.56309065.57
8004033.5800105615
1250514112501007816
Appearance and installation dimensions of the plug - in type front - connected wiring
SJKM1-Moulded-Case-Circuit-Breaker-(MCCB) (3)
Appearance and installation dimensions of plug - in type rear - panel wiring
ModelWLAH1GG1abd
SJKM1-63751351828171550606
SJKM1-125921703850332860566.5
SJKM1-2501071864650334070547
SJKM1-40014428050604048881439
SJKM1-630182300656040531001239
SJKM1-80021229857100431291401439
Outline and Installation Schematic Diagram of Withdrawable Device
SJKM1-Moulded-Case-Circuit-Breaker-(MCCB) (4)
Outline and Installation Dimensions of Withdrawable Device
Model pole overall dimensions installation dimensions
L1L2L3H1H2H3W1W2φd1 ABφd2
SJKM1-400/M3P31033920325317.57748223φ1196134φ6.5
4P31033920325317.57748271φ11144134φ6.5
SJKM1-630/M3P34138121128217.59258253φ13116140φ6.5
4P34138121128217.59258311φ13174140φ6.5
SJKM1-800/M3P367410241238267370289φ13140131φ6.5
4P367410241238267370359φ13210131φ6.5

Frequently Asked Questions

What ambient temperature range can this MCCB operate under?

The circuit breaker can operate normally in an ambient temperature range of -5°C to +40°C. Configurations outside this standard range require special orders.

Does mounting the circuit breaker horizontally or flat reduce its performance?

No. The circuit breaker can be installed horizontally, vertically, or flat without reducing its electrical performance.

What is the difference between release code 200 and code 300?

Code 200 represents the circuit breaker body equipped solely with an electromagnetic release, whereas code 300 features both thermal and electromagnetic releases.

What are the breaking capacity classification types available?

The breaking capacity levels are represented by letters: E for economy type, M for standard type, H for higher reliability type, and L for high breaking type.

What are the differences among N-pole configurations (Type A, B, C, D)?

Type A and Type B have no over-current release element on the N-pole, while Type C and Type D do. Additionally, Type B and C switch synchronously with the three phases, whereas Type A and D remain continuously connected.

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