The Chint NB1L-40 RCBO is a Residual Current Circuit Breaker with Overcurrent Protection (RCBO) designed for leakage protection and personal safety in residential electrical panels, commercial buildings, wet locations (bathrooms, kitchens), outdoor power supplies, and anywhere personal protection is critical. This RCBO combines residual current protection (leakage detection) with overcurrent protection (overload/short-circuit) in a single device, saving space in distribution boards while providing comprehensive circuit protection.
Choose the right sensitivity level for your application:
| Sensitivity | Application | Typical Use |
|---|---|---|
| 10mA / 30mA | Personal Protection | Bathrooms, kitchens, outdoor sockets, medical locations - where human contact risk is highest |
| 100mA | Fire Protection / Indirect Contact | General distribution circuits, sub-panels, areas with indirect contact risk |
| 300mA | Equipment / Fire Protection | Main incoming protection, large installations, industrial equipment protection |
| Type | Detects | When to Use |
|---|---|---|
| Type AC | Pure AC only | Basic residential with standard resistive loads (heaters, incandescent lights). Most economical. |
| Type A (Recommended) | AC + Pulsating DC | Modern homes with electronic loads: washing machines, LED drivers, variable speed tools, computers. Recommended for new installations. |
| Type B | AC + All DC (incl. smooth) | Solar PV systems, EV charging, VFDs, medical equipment, DC-powered installations. Required for DC applications. |
| Parameter | Specification |
|---|---|
| Model Series | NB1L |
| Device Type | RCBO (RCD + MCB) |
| Rated Current | 6A - 125A |
| Pole Configuration | 2P / 4P |
| Residual Sensitivity | 30mA / 100mA / 300mA |
| Detection Type | Type AC (pure AC) |
| Trip Time | ≤30ms at rated residual current |
| Standard | IEC 61008 (RCCB) / IEC 61009 (RCBO) |
Q: What is the difference between RCCB and RCBO?
A: RCCB (Residual Current Circuit Breaker) provides only leakage protection - it detects earth faults and disconnects power but doesn't protect against overloads or short circuits. RCBO (Residual Current Breaker with Overcurrent protection) combines RCD + MCB in one device - it protects against leakage AND overcurrent/overload/short-circuit. RCBO saves space in distribution boards and provides complete protection.
Q: 30mA vs 300mA - which sensitivity should I choose?
A: 30mA (or 10mA) is required for personal protection in locations with high shock risk (bathrooms, kitchens, outdoor power, medical facilities). This level protects humans from fatal electric shock. 300mA is used for equipment and fire protection on main incoming circuits - it prevents fires from insulation faults but won't protect against direct contact. Never use 300mA for socket outlet circuits where people may touch appliances.
Q: Do I need Type A or is Type AC sufficient?
A: For new installations, always choose Type A. Modern appliances (washing machines, LED lights, computers, variable speed tools) generate pulsating DC leakage currents that Type AC cannot detect. Type A provides better safety and is now required by updated electrical codes in many countries. Type AC is only suitable for basic installations with purely resistive loads (heaters, incandescent bulbs) and should be considered legacy technology.
Need Help Selecting RCCB/RCBO? Our electrical engineers can advise on the right sensitivity, type, and rating for your installation. Contact us at sales@sntelec.com or WhatsApp +86-18019187010.
Chint NB1L-40 NB1L-40H Type AC Type A 1P+N 2P 3P 3P+N 4P 6A 10A 16A 20A 25A 32A 40A 30mA 100mA 300mA CHNT RCBO
• Contactors
• Drive contactors
• Welding contactors
• Overload relays
• Starters, open & enclosed
• Manual motor starters
• Softstarters
• Control relays
• Pushbuttons
• Miniature controls
• Control circuit transformers
• Sensors
• Arc Guard systems
| Weight | 0.5 kg |
|---|---|
| Dimensions | 10 × 10 × 10 cm |
| Rated Current |
3A, 25A, 4A, 20A, 1A, 2A, 10A, 16A, 32A, 6A, 40A |
| Rated Voltage |
230V, 380V, 400V |
