Why Choose the Finder 7P.04.8.255.S012 Type 1+2 Surge Protection Device?
The Finder 7P.04.8.255.S012 is a combined Type 1+2 lightning and surge protection device (SPD) designed to protect three-phase electrical installations against lightning impulse currents and transient overvoltages. Part of the Finder 7P Series, this surge arrester provides coordinated lightning current discharge and overvoltage limitation in a single protective assembly.
Designed for three-phase TN-S and TT electrical networks, the Finder 7P.04.8.255.S012 features a five-conductor arrangement covering L1, L2, L3, neutral and protective earth. Its 12.5 kA lightning impulse current rating per protection path, measured using the 10/350 µs waveform, makes it suitable for installations requiring Type 1 lightning current protection. The device also provides a 20 kA nominal discharge current using the 8/20 µs waveform and a 1.5 kV voltage protection level.
Engineered for 40 mm busbar mounting, this combined surge arrester is particularly suited to compatible main electrical distribution assemblies and pre-metering installations where permitted. Its replaceable protection modules, optical fault indication and module retention system support straightforward maintenance and dependable protection in demanding electrical distribution applications.
Key Advantages
- Combined Type 1+2 protection: Provides lightning impulse current discharge and transient overvoltage protection in one device.
- 12.5 kA lightning impulse capability: Designed to handle lightning impulse currents using the 10/350 µs test waveform.
- 20 kA nominal discharge current: Supports protection against transient surge currents using the 8/20 µs waveform.
- 1.5 kV voltage protection level: Helps limit transient overvoltages reaching downstream electrical equipment.
- Three-phase network compatibility: Designed for specified TN-S and TT electrical distribution systems.
- Five-conductor protection arrangement: Suitable for systems incorporating L1, L2, L3, N and PE.
- 40 mm busbar mounting: Enables integration into compatible busbar-based distribution assemblies.
- Replaceable protection modules: Simplifies servicing and replacement of individual protective elements.
- Optical fault indication: Provides local visual indication of protection module condition.
- Module retention system: Helps secure the replaceable protective modules.
- Three-module construction: Provides a defined mounting format for compatible distribution systems.
- No leakage or follow current: Supports reliable operation in the intended electrical installation.
- IP20 ingress protection: Suitable for installation inside appropriately rated electrical distribution enclosures.
- Higher lightning impulse rating: Offers greater impulse current capability than the Finder 7P.04.8.255.S007 variant.
Key Features
- Finder 7P Series lightning and surge protection device.
- Combined Type 1+2 SPD classification.
- Three-phase TN-S and TT network compatibility.
- Five-conductor system: L1, L2, L3, N and PE.
- Four protected conductors excluding protective earth.
- 230 V AC nominal system voltage.
- 255 V AC maximum continuous operating voltage (Uc).
- 12.5 kA lightning impulse current (Iimp) per protection path, 10/350 µs.
- 20 kA nominal discharge current (In), 8/20 µs.
- 1.5 kV voltage protection level (Up).
- 1.5 kV L-N voltage protection level.
- 1.5 kV N-PE voltage protection level.
- 40 mm busbar mounting system.
- Three-module construction.
- Replaceable surge protection modules.
- Optical protection status indication.
- Protection module retention system.
- IP20 ingress protection rating.
- Maximum rigid conductor cross-section of 35 mm².
- Maximum flexible conductor cross-section of 25 mm².
- No integrated backup fuse.
- No remote signalling contact.
- Suitable for specified lightning protection zone transitions.
Technical Specifications
- Manufacturer: Finder
- Series: 7P Series
- Model: 7P.04.8.255.S012
- Manufacturer part number: 7P.04.8.255.S012
- Product type: Combined lightning and surge arrester
- SPD classification: Type 1+2
- Electrical system: Three-phase AC
- Compatible earthing systems: TN-S and TT
- System conductors: L1, L2, L3, N and PE
- Number of conductors excluding earth: 4
- Nominal system voltage: 230 V AC
- Maximum continuous operating voltage (Uc): 255 V AC
- Lightning impulse current (Iimp), 10/350 µs: 12.5 kA per protection path
- Nominal discharge current (In), 8/20 µs: 20 kA
- Voltage protection level (Up): 1.5 kV
- Voltage protection level L-N: 1.5 kV
- Voltage protection level N-PE: 1.5 kV
- Mounting method: Busbar mounting
- Compatible busbar system: 40 mm
- Construction size: 3 modular units
- Protection modules: Replaceable
- Module retention system: Yes
- Status indication: Optical
- Remote signalling contact: No
- Integrated backup fuse: No
- Maximum rigid conductor cross-section: 35 mm²
- Maximum flexible conductor cross-section: 25 mm²
- Ingress protection: IP20
- Unprotected outdoor installation: Not suitable
- Typical installation position: Main distribution or pre-metering area where permitted
- Lightning protection zone application: LPZ 0 to LPZ 1 transition
- Country of origin: Czech Republic
- EAN: 8012823429724
Reliable Lightning and Surge Protection for Three-Phase Electrical Distribution
Electrical installations can experience transient overvoltages caused by direct or indirect lightning activity, electrical switching operations and disturbances within the supply network. These events may damage sensitive electronic equipment, interrupt industrial processes and compromise electrical system reliability. The Finder 7P.04.8.255.S012 Type 1+2 surge protection device is designed to reduce these risks by discharging high-energy surge currents and limiting the voltage reaching downstream equipment.
With a 12.5 kA lightning impulse current rating per protection path, the device provides enhanced lightning current handling capability for suitable installations. Its combined Type 1+2 classification enables use at the transition between lightning protection zones, including LPZ 0 and LPZ 1, where both lightning current discharge and transient overvoltage protection are required.
The 40 mm busbar mounting arrangement supports integration into compatible electrical distribution assemblies, while the replaceable protective modules and optical status indication simplify inspection and maintenance. The device is intended for specified TN-S and TT earthing systems and should be selected in accordance with the installation's lightning protection requirements, prospective fault current, upstream protective devices and applicable electrical regulations.
For effective surge protection, installation should minimise the length of connecting conductors and ensure suitable coordination with any downstream SPDs. Any required external backup protection must be selected according to Finder's installation instructions. Installation and servicing must be carried out by a suitably qualified electrician.
Typical Applications
- Three-phase TN-S electrical distribution networks.
- Three-phase TT electrical distribution networks.
- Main electrical distribution boards and switchgear assemblies.
- Incoming electrical supply lightning and surge protection.
- Compatible 40 mm busbar distribution systems.
- Commercial and industrial building electrical infrastructure.
- Pre-metering surge protection installations where permitted.
- Lightning protection zone transition points.
- Electrical installations requiring combined Type 1 and Type 2 protection.
- Industrial automation and control system supply protection.
- Electrical distribution systems serving sensitive electronic equipment.
- Building services and infrastructure protection.
- OEM electrical distribution and panel-building applications.
