Designed for precision protection at the point of use, the KPB385-40 Series is a Type 3 /Class III Surge Protection Device(SPD) that acts as a final barrier against high-frequency transients and residual surges in low-voltage AC power systems.
With a tested discharge capacity of 40 kA (8/20 μs), this compact SPD is optimized for installation near sensitive loads—such as control units, smart meters, networking gear, and industrial electronics—where even minor voltage spikes can lead to malfunctions or long-term degradation.
Built with a space-saving modular housing, the KPB385-40 ensures fast, tool-free DIN rail mounting in sub-panels or equipment cabinets. Its ultra-fast 25 ns response time enables immediate clamping of transient overvoltages, while integrated thermal disconnection and overcurrent protection guarantee safe operation under fault conditions.
Unlike primary or secondary SPDs, the KPB385-40 focuses on fine-level protection, making it ideal for Stage 3 (final circuit) applications in single-phase and three-phase installations. It complements upstream Type 1 and Type 2 protectors to complete a coordinated, multi-layered surge defense strategy.
1-Phase & 3-Phase systems
Type 3/Class III SPD for final-stage surge protection
40 kA (8/20 μs) discharge capacity
Ultra-fast response to eliminate residual transients
Modular design with overcurrent and thermal protection
Visual status indicator for easy maintenance (optional)
35mm DIN rail mounting for quick installation
Space-saving and cost-effective
Near sensitive equipment: PLCs, servers, and control systems
In sub-distribution panels or local power outlets
For protection of smart home devices and IoT systems
At the end of circuits in offices, homes, and industrial machines
Where fine-level surge suppression is required
- Installation must be carried out under power-off conditions. Secure the surge protector KPB385-40 and circuit breaker to the rail respectively, and connect L, N, PE, etc. as shown in the diagram.
- Regularly check the working status of the surge protector. Replace the product immediately if it fails or is damaged.
| Electrical | ||
Model | KPB385-4020 | KPB385-4011 |
Number of Positions | 2-pos. | 2-pos. |
SPD Type per UL 1449 3rd Edition | Type 3 | Type 3 |
SPD Class per IEC 61643-11 | Class III | Class III |
Nominal Operating AC Voltage[Un] | 100-240 V (50/60 Hz) | 100-240 V (50/60 Hz) |
Max. Continuous Operating AC Voltage[Uc] | 385 V (50/60 Hz) | 385 V (50/60 Hz) |
Response time[tA] | ≤ 25 ns | ≤ 25 ns |
Nominal Discharge Current [In] | 20 kA (8/20 μs) | 20 kA (8/20 μs) |
Maximum Discharge Current [lmax] | 40 kA (8/20 μs) | 40 kA (8/20 μs) |
Protection Mode | L/N-G | L/N, N-G |
Voltage Protection Level [Up] | 1500 V | 1500 V |
Degradation Failure Iindication | Red - failure,Green - Normal | Red - failure,Green - Normal |
Remote Signal Contact | Optional | Optional |
Model | KPB385-4040 | KPB385-4031 |
Number of Positions | 4-pos. | 4-pos. |
SPD Type per UL 1449 3rd Edition | Type 3 | Type 3 |
SPD Class per IEC 61643-11 | Class III | Class III |
Nominal Operating AC Voltage[Un] | 208-415 V (50/60 Hz) | 208-415 V (50/60 Hz) |
Max. Continuous Operating AC Voltage[Uc] | 385 V (50/60 Hz) | 385 V (50/60 Hz) |
Response time[tA] | ≤ 25 ns | ≤ 25 ns |
Nominal Discharge Current [In] | 20 kA (8/20 μs) | 20 kA (8/20 μs) |
Maximum Discharge Current [lmax] | 40 kA (8/20 μs) | 40 kA (8/20 μs) |
Protection Mode | L1/l2/L3/N-G | L1/l2/L3/N-G |
Voltage Protection Level [Up] | 1500 V | 1500 V |
Degradation Failure Iindication | Red - failure,Green - Normal | Red - failure,Green - Normal |
Remote Signal Contact | Optional | Optional |
| Mechanical | ||
Connection Mode | Parallel | |
Wiring diameter | 4-25 mm² | |
Mounting Method | 35mm DIN-rail | |
Housing Material | Thermoplastic,Extinguishing Degree UL94 V 0 | |
Environmental Ingress Protection Rating | IP20 | |
Enclosure Color | Black | |
Operating Temperature (℃) | -40 ℃ to +80 ℃ | |
Dimensions (L×W×H) | 1-Phase: 90 × 36 × 65 mm 3-Phase: 90 × 72 × 65 mm | |
Weight | 1-Phase: 175 g 3-Phase: 350 g | |
| Standards Compliance&Certifications | ||
Standards | UL 1449 3rd Edition: 2011, IEC 61643-11: 2011, EN 61643-11:2012, IEEE C62.11: 2005, IEEE C62.41: 2002, IEEE C62.45: 2002, NEMA LS-1 | |
| Certifications | CE | |
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