Why Choose the Finder 7P.25.8.150.1015 Type 2 Three-Phase Surge Protection Device?
The Finder 7P.25.8.150.1015 is a four-pole, Type 2 surge protection device (SPD) designed to protect compatible three-phase electrical installations with a neutral conductor against transient overvoltages. Part of the Finder Series 7P surge protection range, this DIN rail-mounted surge arrester incorporates four metal oxide varistor protection elements and is specifically intended for suitable TN-S electrical distribution systems.
Designed for three-phase installations operating at a nominal phase-to-neutral voltage of 120 V AC, the Finder 7P.25.8.150.1015 features a 150 V AC maximum continuous operating voltage (Uc), a 20 kA nominal discharge current (In) and a 40 kA maximum discharge current (Imax), measured using an 8/20 µs surge waveform. Its 0.74 kV voltage protection level (Up) helps limit transient overvoltages reaching connected equipment when the SPD is correctly installed and coordinated with the electrical system.
The device features replaceable varistor protection cartridges, integrated optical status indication and a remote signalling changeover contact for external monitoring of surge protection status. Its compact four-module construction, standard 35 mm DIN rail mounting and IP20 protection rating make it suitable for industrial control cabinets, three-phase distribution boards and electrical installations where dependable surge protection and straightforward maintenance are essential.
Key Advantages
- Type 2 surge protection helps protect electrical installations against induced lightning surges and switching transients.
- Four-pole configuration provides protection for L1, L2, L3 and neutral-to-earth paths in compatible TN-S systems.
- 150 V AC maximum continuous operating voltage for correctly specified low-voltage three-phase installations.
- 20 kA nominal discharge current provides substantial surge-handling capability.
- 40 kA maximum discharge current supports protection against higher-energy transient events.
- 0.74 kV voltage protection level helps reduce transient voltages reaching connected electrical equipment.
- Four metal oxide varistor protection elements provide coordinated surge-limiting functionality across the protected conductors.
- Replaceable varistor cartridges allow individual protective modules to be serviced without replacing the complete SPD assembly.
- Optical status indicators simplify routine inspection and maintenance.
- Integrated remote signalling contact enables surge protection status monitoring through a suitable alarm or control system.
- Four-module DIN rail format provides a compact solution for three-phase electrical distribution boards.
- −40 to +80 °C operating temperature range supports demanding industrial environments.
- IP20 ingress protection rating for installation within suitable electrical enclosures.
Key Features
- Finder Series 7P surge protection device.
- 7P.25 four-pole Type 2 SPD configuration.
- Three-phase plus neutral protection for compatible TN-S systems.
- Four metal oxide varistor (MOV) protection elements.
- 120 V AC nominal phase-to-neutral system voltage.
- 150 V AC maximum continuous operating voltage (Uc).
- 20 kA nominal discharge current (In) using an 8/20 µs waveform.
- 40 kA maximum discharge current (Imax) using an 8/20 µs waveform.
- 0.74 kV voltage protection level (Up).
- Replaceable varistor protection cartridges for simplified maintenance.
- Optical protection status indication for identifying cartridges requiring replacement.
- Integrated SPDT remote signalling contact for external status monitoring.
- Four-module DIN rail construction.
- 35 mm DIN rail mounting in accordance with EN 60715.
- IP20 protection rating.
- −40 to +80 °C ambient operating temperature range.
- 50 kA short-circuit current rating (Isccr) under specified installation conditions.
- Maximum associated backup fuse of 160 A, subject to the manufacturer's coordination requirements.
- IEC/EN 61643-11 Type 2 surge protection classification.
- Suitable for installation at the LPZ 1 / LPZ 2 boundary within an appropriately coordinated surge protection system.
Technical Specifications
- Manufacturer: Finder
- Series: 7P Surge Protection Devices
- Model: 7P.25.8.150.1015
- Product type: Three-phase Type 2 surge protection device
- SPD classification: Type 2
- Number of protected conductors: 4
- Electrical configuration: Three-phase plus neutral
- Suitable earthing arrangement: TN-S
- Protection arrangement: L1-PE, L2-PE, L3-PE and N-PE
- Protection technology: Four metal oxide varistors (MOV)
- Nominal phase-to-neutral voltage (Un): 120 V AC
- Maximum continuous operating voltage (Uc): 150 V AC
- Nominal discharge current (In): 20 kA (8/20 µs)
- Maximum discharge current (Imax): 40 kA (8/20 µs)
- Voltage protection level (Up): 0.74 kV
- Short-circuit current rating (Isccr): 50 kA, subject to specified installation conditions
- Maximum associated backup fuse: 160 A, subject to manufacturer coordination requirements
- Protection elements: Replaceable varistor cartridges
- Local status indication: Optical varistor status indicators
- Remote signalling: Yes
- Remote signalling contact configuration: 1 CO (SPDT)
- Remote contact rated current: 0.5 A AC / 0.1 A DC
- Remote contact rated voltage: 250 V AC / 30 V DC
- Mounting method: DIN rail
- DIN rail size: 35 mm
- DIN rail standard: EN 60715
- Installation space: 4 modular spacing units
- Ingress protection: IP20
- Operating temperature: −40 to +80 °C
- Applicable standard: IEC/EN 61643-11
- Typical installation location: LPZ 1 / LPZ 2 boundary
- EAN / GTIN: 8012823453439
Reliable Type 2 Surge Protection for Three-Phase TN-S Systems
Three-phase electrical installations can experience transient overvoltages caused by switching operations, inductive loads, power network disturbances and lightning-related events. These short-duration voltage surges can damage electronic control equipment, interrupt industrial processes and reduce the reliability of connected electrical systems. A correctly selected three-phase Type 2 surge protection device helps limit these transient voltages and reduce the risk of equipment damage.
The Finder 7P.25.8.150.1015 is designed for compatible three-phase TN-S installations with a neutral conductor. Its four-pole protection arrangement uses metal oxide varistors to provide surge protection between the three phase conductors and protective earth, as well as between neutral and protective earth.
With a 150 V AC maximum continuous operating voltage, the device is intended for lower-voltage three-phase installations rather than conventional 230/400 V AC mains distribution systems. Correct selection of the SPD operating voltage is essential because an incorrectly rated surge protector may fail to provide the intended protection or may be damaged by the normal supply voltage.
The Finder 7P.25.8.150.1015 provides a 20 kA nominal discharge current and a 40 kA maximum discharge current, both tested using the standard 8/20 µs surge waveform. Its 0.74 kV voltage protection level indicates the device's ability to limit transient overvoltages under the applicable test conditions. Actual protection at connected equipment also depends on the installation arrangement, conductor lengths, earthing system and coordination with other protective devices.
The device's replaceable varistor cartridges support convenient maintenance. Each protection element incorporates optical status indication, allowing maintenance personnel to identify when a cartridge is no longer serviceable. The integrated remote signalling changeover contact can be connected to a suitable PLC input, building management system or alarm circuit, enabling external monitoring of the SPD condition.
Installation is straightforward using a standard 35 mm DIN rail, with the complete assembly occupying four modular spacing units. The SPD should be installed by a qualified electrical professional in accordance with Finder's instructions, applicable electrical regulations and the requirements of the electrical distribution system.
Remote Status Monitoring and Replaceable Varistor Modules
In industrial installations, surge protection equipment may be installed in distribution cabinets that are not inspected frequently. The Finder 7P.25.8.150.1015 addresses this maintenance requirement through a combination of local optical status indication and an integrated remote signalling contact.
The visual indicators provide an immediate indication of the condition of the varistor protection elements during routine inspections. When a cartridge reaches the end of its service life, the corresponding replacement module can be fitted while retaining the existing SPD base, provided the base remains serviceable and the replacement cartridge is correctly matched.
The remote signalling contact provides a changeover output suitable for connection to an external monitoring circuit. With a specified contact rating of 0.5 A at 250 V AC or 0.1 A at 30 V DC, the contact can be incorporated into appropriately designed alarm and monitoring systems.
This combination of local and remote indication helps maintenance teams identify protection faults promptly and supports preventative maintenance strategies in industrial electrical installations.
Typical Applications
- Compatible low-voltage three-phase TN-S electrical distribution systems.
- Three-phase industrial electrical control cabinets.
- Electrical distribution boards with separate neutral and protective earth conductors.
- Industrial automation and PLC control systems.
- Manufacturing equipment and machinery electrical supplies.
- Motor control centres and industrial process installations.
- Commercial and industrial building electrical infrastructure.
- Electrical installations exposed to induced lightning surges.
- Three-phase systems requiring protection against switching transients.
- Electrical panels requiring remote surge protection status monitoring.
- DIN rail-mounted surge protection in industrial enclosures.
- Maintenance-friendly electrical distribution systems using replaceable SPD cartridges.
