Why Choose the Finder 7P.23.8.275.0020 Type 2 Surge Protection Device?
The Finder 7P.23.8.275.0020 is a three-pole Type 2 surge protection device (SPD) designed to protect three-phase TN-C electrical distribution systems against transient overvoltages caused by switching operations and induced lightning surges. Part of the Finder 7P Series, this surge arrester features three metal oxide varistor protection paths and a compact DIN rail-mounted construction.
Designed for 230/400 V AC three-phase TN-C installations, the Finder 7P.23.8.275.0020 provides protection between the L1, L2 and L3 phase conductors and the combined protective earth and neutral (PEN) conductor. It has a 275 V AC maximum continuous operating voltage (Uc), a 20 kA nominal discharge current (In) and a 40 kA maximum discharge current (Imax), measured using the 8/20 µs surge waveform.
The device combines replaceable varistor cartridges with local optical condition indication, allowing maintenance personnel to identify when a protective module requires replacement. This .0020 version does not include a remote signalling contact, making it suitable for installations where local inspection is sufficient.
Key Advantages
- Type 2 surge protection: Helps protect electrical equipment against induced lightning surges and switching transients.
- Three-phase TN-C compatibility: Designed for systems using a combined protective earth and neutral conductor.
- Three-pole protection: Provides varistor-based surge protection between L1, L2 and L3 and PEN.
- 20 kA nominal discharge current: Offers substantial transient surge current handling capability.
- 40 kA maximum discharge current: Supports protection against higher-energy surge events.
- 275 V AC continuous operating voltage: Suitable for the specified 230/400 V AC distribution system.
- 1.2 kV voltage protection level: Helps limit transient overvoltages reaching connected equipment.
- Replaceable varistor modules: Simplifies maintenance without replacing the complete SPD assembly.
- Visual status indication: Provides local Healthy/Replace indication of the protective elements.
- 35 mm DIN rail mounting: Supports installation in standard electrical distribution enclosures.
- Compact three-module construction: Occupies approximately 53.8 mm of DIN rail width.
- Wide operating temperature range: Suitable for operation from −40 to +80 °C.
- IP20 ingress protection: Suitable for installation within appropriately rated electrical enclosures.
Key Features
- Finder 7P Series surge protection device.
- Type 2 SPD classification.
- Three-pole, 3+0 protection configuration.
- Three metal oxide varistor protection paths.
- Compatible with three-phase TN-C networks.
- 230 V AC nominal phase voltage.
- 275 V AC maximum continuous operating voltage (Uc).
- 350 V DC maximum continuous operating voltage rating.
- 20 kA nominal discharge current (In), 8/20 µs.
- 40 kA maximum discharge current (Imax), 8/20 µs.
- 1.2 kV voltage protection level (Up).
- 0.9 kV voltage protection level at 5 kA.
- 25 ns varistor response time.
- Replaceable varistor cartridges.
- Replacement module: Finder 7P.20.8.275.0020.
- Optical Healthy/Replace status indication.
- No remote signalling contact.
- 35 mm DIN rail mounting according to EN 60715.
- Three DIN-module construction.
- IP20 ingress protection.
- Compliance with EN 61643-11:2012.
Technical Specifications
- Manufacturer: Finder
- Series: 7P Series
- Model: 7P.23.8.275.0020
- Manufacturer part number: 7P.23.8.275.0020
- Product type: Surge protection device
- SPD classification: Type 2
- Electrical system: Three-phase AC
- Compatible earthing system: TN-C
- Number of poles: 3
- Protection configuration: 3+0
- Protection arrangement: L1-PEN, L2-PEN, L3-PEN
- Protection technology: Metal oxide varistor
- Nominal system voltage: 230/400 V AC
- Nominal phase voltage (Un): 230 V AC
- Maximum continuous operating voltage (Uc), AC: 275 V AC
- Maximum continuous operating voltage (Uc), DC: 350 V DC
- Nominal discharge current (In), 8/20 µs: 20 kA
- Maximum discharge current (Imax), 8/20 µs: 40 kA
- Voltage protection level (Up): 1.2 kV
- Voltage protection level at 5 kA (Up5): 0.9 kV
- Response time: 25 ns
- Short-circuit current rating (ISCCR): 50 kA
- Maximum upstream fuse rating: 160 A gL/gG
- Protection modules: Replaceable varistor cartridges
- Replacement module code: 7P.20.8.275.0020
- Local status indication: Optical Healthy/Replace indicator
- Remote signalling contact: No
- Mounting method: 35 mm DIN rail
- Mounting standard: EN 60715
- Modular width: 3 DIN modules
- Approximate overall width: 53.8 mm
- Solid conductor cross-section: 1–35 mm²
- Flexible conductor cross-section: 1–25 mm²
- Wire stripping length: 12 mm
- Terminal tightening torque: 3 Nm
- Operating ambient temperature: −40 to +80 °C
- Ingress protection: IP20
- Applicable standard: EN 61643-11:2012
- EAN: 8012823400815
Three-Phase TN-C Surge Protection for Electrical Distribution Systems
Electrical distribution networks can experience transient overvoltages resulting from lightning activity, switching operations and disturbances on the electrical supply. These short-duration voltage peaks can damage sensitive electronics, interrupt machinery operation and reduce the reliability of electrical installations. The Finder 7P.23.8.275.0020 Type 2 surge arrester is designed to limit these overvoltages in compatible three-phase TN-C systems.
Its three metal oxide varistor protection paths connect the phase conductors to the combined PEN conductor. During a transient surge event, the varistors respond rapidly to divert surge current and limit the voltage appearing across the protected circuit. The device's 20 kA nominal discharge current and 40 kA maximum discharge current support protection against induced lightning surges and electrical switching transients.
The Finder 7P.23.8.275.0020 is intended for installation at suitable surge protection zone boundaries, including LPZ 1 to LPZ 2, and can form part of a coordinated surge protection system. Its DIN rail-mounted construction makes it suitable for electrical distribution boards and control panels where space-efficient installation is required.
The replaceable Finder 7P.20.8.275.0020 varistor cartridges support straightforward maintenance when the visual Healthy/Replace indicator shows that a protective module has reached the end of its service life. The .0020 version provides local indication only; applications requiring remote status monitoring should use an appropriately specified Finder variant.
Installation consideration: This SPD is intended for TN-C systems with a combined PEN conductor and must not be assumed suitable for TT or TN-S installations with separate neutral and protective earth connections. Upstream protection, prospective short-circuit current, conductor lengths and coordination with other SPDs must be checked against the manufacturer's instructions. Installation should be carried out by a suitably qualified electrician.
Typical Applications
- Three-phase TN-C electrical distribution networks.
- Main and secondary electrical distribution boards.
- Industrial electrical switchgear assemblies.
- Commercial building electrical infrastructure.
- Industrial automation and machinery supply protection.
- Electrical installations using a combined PEN conductor.
- Type 2 surge protection at LPZ 1 to LPZ 2 boundaries.
- Electrical control panels and distribution cabinets.
- Building services electrical distribution systems.
- Lift and escalator electrical supply protection.
- Road and tunnel lighting distribution infrastructure.
- Industrial maintenance and electrical panel-building applications.
