Claire
Mr.Fu
Claire
China SJKM1LY Auto Reclosing Molded Case Circuit Breaker - Reliable Suppliers & Factory for Intelligent Protection Solutions
Type Designation
| 1 | Manufacturer Code |
| 2 | Intelligent Circuit Breaker |
| 3 | Design Serial Number |
| 4 | With Residual Current Protection |
| 5 | Rated Frame Current Level |
| 6 | Three-phase Four-wire (3P+N) |
| 7 | Function Extension: None: Economy Type (Overcurrent Non-adjustable) S: Standard Type (Overcurrent Adjustable) |
Product Display
Technical Parameters
| Model Specification | M1LY-125A | M1LY-250A | M1LY-400A | M1LY-630A | M1LY-800A | |
| Number of Poles | 3P+N | 3P+N | 3P+N | 3P+N | 3P+N | |
| Frame Current (A) | 125A | 250A | 400A | 630A | 800A | |
| Rated Operational Voltage Ue (V) | AC400 50Hz | |||||
| Rated Insulation Voltage Ui (V) | 1000V | |||||
| Rated Impulse Withstand Voltage Uimp (kV) | 8 | |||||
| Arc Distance (mm) | ≥50 | ≥50 | ≥100 | ≥100 | ≥100 | |
| Ultimate Short-circuit Breaking Capacity Icu (kA) | 50 | 50 | 35 | 35 | 65 | |
| Service Short-circuit Breaking Capacity Ics (kA) | 35 | 35 | 25 | 25 | 65 | |
| Utilization Category | B | A | B | B | B | |
| Rated Short-time Withstand Current Icw (kA/s) | 5kA/0.5s | 3kA/1s | 5kA/1s | 5kA/1s | 8kA/1s | |
| Rated Residual Short-circuit Making and Breaking Capacity Icm (kA) | ≥5%Icu | |||||
| Residual Current Operating Characteristics | AC Type | |||||
| Rated Residual Operating Current I△n | 50-1000mA（Adjustable） | 50-900mA （Step Adjustable） | 50-1000mA（Adjustable） | |||
| Auto-reclosing Time (s) | 20s-60s | |||||
| Operating Performance (operations) | Energized | 1500 | 1000 | 1000 | 1000 | 500 |
| De-energized | 8500 | 7000 | 4000 | 4000 | 2500 | |
| Total Operations | 10000 | 8000 | 5000 | 5000 | 3000 | |
| Delay Time (ms) | ≤40ms | |||||
| Communication Delay Time (ms) | ≤200ms | |||||
| Lockout Time | 10s-250s | |||||
Operating Performance of the Release
1. Overload Protection Characteristics (Inverse Time Delay Operation)
| Rated Operating Current of the Release (A) | Release (Ambient Temperature 40℃) | |
| 1.05In (Cold State) | 1.30In (Hot State) | |
| In≤63A | No operation for ≥1h | Operation in <1h |
| In>63A | No operation for ≥2h | Operation in <2h |
Calculation of overload long-delay time: T1 = (6lr/1)² × Tr1
2. Setting Value of Instantaneous Overcurrent Release Current
| Rated Current of Integrity Level Inm (A) | Rated Current Multiple | Conventional Time |
| 100 | 10 In±20% | <0.2s |
| 250 | 10 In±20% | <0.2s |
| 400 | 10 In±20% | <0.2s |
| 630 | 10 In±20% | <0.2s |
| 800 | 10 In±20% | <0.2s |
Overall Dimensions and Installation Dimensions
| Model | Overall Dimensions | Installation Dimensions | Mounting Screw Cutout Dimensions (mm) | ||||||||||
| L | W | H | H1 | H2 | L2 | L3 | W2 | W3 | W4 | L1 | W1 | ||
| 100 Type | 231 | 120 | 118 | 62 | 50 | 264.6 | 213.5 | 30 | 30 | 30 | 211 | 60 | A4×40 |
| 250 Type | 240.5 | 141 | 136.5 | 83 | 47.5 | 300.3 | 220.1 | 35.1 | 35.1 | 35.1 | 201.5 | 70 | A4×45 |
| 400 Type | 335 | 195 | 186.5 | 97.5 | 83 | 380.2 | 303 | 47.8 | 47.8 | 60.3 | 272 | 93.5 | A5×60 |
| 630 Type | 355.5 | 240.5 | 194.5 | 105 | 83 | 396.6 | 319.45 | 58 | 58 | 70.5 | 284 | 116 | A5×65 |
| 800 Type | 355.5 | 240.5 | 194.5 | 105 | 83 | 396.6 | 319.45 | 58 | 58 | 70.5 | 284 | 116 | A5×65 |
Frequently Asked Questions
What is the SJKM1LY Auto-Reclosing Molded Case Circuit Breaker used for?
The SJKM1LY is an intelligent molded case circuit breaker with auto-reclosing function and residual current protection. It is designed for overload, short-circuit, and earth-fault protection in three-phase four-wire (3P+N) power distribution systems, supporting rated frame currents from 125A to 800A.
What is the auto-reclosing time range for the SJKM1LY circuit breaker?
The auto-reclosing time is adjustable within the range of 20s to 60s, allowing flexible configuration based on the specific application requirements of the power system.
What rated residual operating current (I△n) options are available?
For the 125A and 800A models, the rated residual operating current is continuously adjustable from 50mA to 1000mA. For the 250A, 400A, and 630A models, it is step-adjustable in the range of 50mA to 900mA, accommodating different levels of residual current sensitivity.
What is the difference between the Economy Type and Standard Type in the type designation?
According to the type designation, the Economy Type (no suffix) features non-adjustable overcurrent settings, while the Standard Type (suffix "S") provides adjustable overcurrent settings, offering greater flexibility for diverse load protection requirements.
What is the ultimate short-circuit breaking capacity (Icu) of the SJKM1LY series?
The Icu varies by model: the 125A and 250A models offer 50kA, the 400A and 630A models offer 35kA, and the 800A model offers the highest capacity at 65kA, ensuring reliable protection under severe short-circuit conditions.
What is the rated operational voltage and insulation voltage of this circuit breaker?
The SJKM1LY series operates at a rated voltage of AC 400V / 50Hz across all models. The rated insulation voltage (Ui) is 1000V, and the rated impulse withstand voltage (Uimp) is 8kV, ensuring reliable insulation performance in demanding electrical environments.