Why DC Combiner Box Is Essential for PV Systems
If you're a solar system buyer, installer, or project manager, let's get straight to the point—you're here because you need a definitive answer: Does your solar system really need a DC combiner box? A

• Application: remote making & breaking circuits;protect circuit from over-load when assembling with thermal over-load relay; Frequent start-up and control of AC contactor.
• Electric ratings: AC50/60Hz,690V,up to 95A.
• Utilization category:AC-3,AC-4; Altitude:≤2000m.
• Ambient temperature:-5°C~+40°C.
• Mounting conditions: inclination between the mounting plane and the verticalplane should not exceed ±5.




| PRODUCT MODEL | SCJ8 | |||||||||||
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| Product Name | SCJ8-0911 | SCJ8-1211 | SCJ8-1811 | SCJ8-2511 | SCJ8-3111 | |||||||
| Number of Poles | 3P | 3P | 3P | 3P | 3P | |||||||
| Rated operational current(A) | 380V | AC-3 | 3 | 12 | 18 | 25 | 32 | |||||
| AC-4 | 3.5 | 5 | 7.7 | 8.5 | 12 | |||||||
| 660V | AC-3 | 6.6 | 8.9 | 12 | 18 | 21 | ||||||
| AC-4 | 1.5 | 2 | 3.8 | 4.4 | 7.5 | |||||||
| Conventional thermal current (Ith) | A | 20 | 25 | 32 | 40 | 50 | ||||||
| Rated insulation voltage (Ui) | V | 690 | 690 | 690 | 690 | 690 | ||||||
| Power of controlled 3-phase cage motor(AC-3) | 220V | 2.2 | 3 | 4 | 5.5 | 7.5 | ||||||
| 380V | 4 | 5.5 | 7.5 | 11 | 15 | |||||||
| 660V | 5.5 | 7.5 | 9 | 15 | 18.5 | |||||||
| Operational frequency (Operations/h) | Electrical | AC-3 | 1200 | 1200 | 1200 | 1200 | 600 | |||||
| Mechanical | AC-4 | 300 | 300 | 300 | 300 | 300 | ||||||
| 3600 | 3600 | 3600 | 3600 | 3600 | ||||||||
| Electrical life (x 10⁴ operations) | AC-3 | 100 | 100 | 100 | 100 | 80 | ||||||
| AC-4 | 20 | 200 | 20 | 20 | 20 | |||||||
| Electrical life (x 10⁴ operations) | 1000 | 1000 | 1000 | 100 | 800 | |||||||
| Matched fuse type | RT16-20 | - | RT16-32 | RT16-40 | RT16-50 | |||||||
| Terminals | Number of piece | 1 | 2 | 1 | 2 | 1 | 2 | 1 | 2 | 1 | 2 | |
| Flexible cable without cable end |
mm² | 1/2.5 | 1/2.5 | 1/2.5 | 1/2.5 | 1.5/4 | 1.5/4 | 1/2.5 | 1/2.5 | 2.5/6 | 2.5/6 | |
| Flexible cable without cable end |
mm² | 1/4 | 1/4 | 1/4 | 1/2.5 | 1.5/6 | 1.5/4 | 1/4 | 1/2.5 | 2.5/10 | 2.5/6 | |
| Inflexible cable | mm² | 1/4 | 1/4 | 1/4 | 1/4 | 1.5/6 | 1.5/6 | 1/4 | 1/4 | 2.5/10 | 2.5/10 | |
| AC coil power 50Hz | In-rush | VA | 70 | 70 | 70 | 110 | 110 | |||||
| Sealed | VA | 9.0 | 9.0 | 9.5 | 14.0 | 14.0 | ||||||
| Power | W | 1.8-2.7 | 1.8-2.7 | 3-4 | 3-4 | 3-4 | ||||||
| Operating range | ||||||||||||
| Auxiliary contact | ||||||||||||


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