12.5kA High-Energy 3+1 Protection Structure for Building and Data Center Applications

Product Overview

The NPS01-FBC12.5 AC 3+1P Surge Protective Device is a Type 1+2 combined high-current surge protection solution designed for three-phase four-wire power distribution systems. It complies with EN/IEC 61643-11 and GB/T 18802.11 standards and provides Class I+II protection performance.

The product adopts a standard 3+1 configuration consisting of three phase protection modules and one neutral protection module. The L1/L2/L3 phases provide individual protection to ground, while the N-PE circuit uses a dedicated high-capacity discharge module.

With an impulse current capability of 12.5kA (10/350μs), it is designed for high lightning risk environments and is widely used at the incoming power side of buildings, communication rooms, data centers, electrical systems, and industrial facilities.

The 72mm modular structure supports 35mm DIN rail installation, with Uc voltage options from 275V to 440V.

Dedicated N-PE High-Current Spark Gap for Stable Neutral

The phase protection circuit combines large graphite spark gaps with high-energy zinc oxide varistors, while the N-PE path uses a dedicated high-current graphite discharge module.

During normal operation, the neutral line maintains extremely low leakage current and power consumption, helping prevent abnormal neutral voltage rise and improving system stability.

The coordinated protection structure effectively manages lightning impulses and switching overvoltage without continuous current flow.

High-quality components are carefully selected and tested for temperature resistance, humidity resistance, and aging durability.

The conductive path uses T2 copper busbars with tin-plated surfaces, providing strong current carrying capability, low resistance, and reduced heat generation.

The UL94V-0 flame-retardant housing ensures reliable insulation protection. Automated welding, module assembly, and 100% high-current impulse testing provide consistent product quality.

Independent Thermal Disconnection for Reliable System Operation

The device provides 20kA (8/20μs) nominal discharge current and 50kA maximum discharge current. The voltage protection level reaches 1.2kV, with a response time of ≤25ns (100ns in NPE mode).

Each module features independent thermal disconnection and a red/green status indicator. Green indicates normal operation, while red indicates the specific module requires replacement.

The independent module structure ensures that a single module fault does not affect the operation of other protection paths.

Optional remote alarm contacts support AC 250V/0.5A output and can be connected to building automation, power monitoring, or centralized control systems.

Operating from -40℃ to +80℃ with 5%-95% humidity tolerance, and compatible with 4-25mm² conductors, this product provides a reliable high-current protection solution for three-phase four-wire systems.

Model	NPS01-FBC12.5/275/3+1	NPS01-FBC12.5/320/3+1	NPS01-FBC12.5/385/3+1	NPS01-FBC12.5/440/3+1
SPD Test Category	Type1+2/ClassI+II(EN/IEC61643-11,GB/T18802.11)
Maximum Continuous Operating Voltage Uc (Current Type: a.c.)	275V(NPE255V)	320V(NPE255V)	385V(NPE255V)	440V(NPE255V)
Lightning Impulse Current (10/350μs) [L-PE, N-PE] Iimp	12.5kA	12.5kA	9kA	9kA
Nominal Discharge Current (8/20μs) [L-PE, N-PE] In	20kA
Maximum Discharge Current (8/20μs) [L-PE, N-PE] Imax	50kA
Voltage Protection Level [L-PE, N-PE] Up	1.2kV	1.3kV	1.5kV	1.7kV
Response Time	≤25ns (N-PE: 100ns)
Backup Fuse	160A gG Fuse
Remote Signal Alarm	Normally Open and Normally Closed Contact Terminals
Remote Alarm Signal Energy Un/In	AC: 250V/0.5A; 125V/1A; DC: 30V/0.1A
Remote Alarm Signal Connection Wire	0.5mm² to 1.5mm²
Remote Contact Type	Floating Changeover Contact
Temperature and Humidity Range	-40℃ to +80℃; 5%~95%
Disconnector Operation Indicator	Red: Failed; Green: Normal
Minimum Installation Conductor Cross-Section Area (L, N, PE)	4mm² Solid Wire / Flexible Wire
Maximum Installation Conductor Cross-Section Area (L, N, PE)	25mm² Standard Wire / Flexible Wire
Installation Method	35mm Standard DIN Rail
Enclosure Material	440
Enclosure Protection Degree	IP20
Dimensions	W×L×H: 72×87×87mm
Note: The above products can be optionally equipped with a remote signaling function. Products with remote signaling will have "/FM" added after the original model number, such as NPS01-FBC7/275/1/FM.