Why Choose the Finder 7P.21.8.440.1020 Type 2 Surge Protection Device with Remote Signalling?
The Finder 7P.21.8.440.1020 is a single-pole Type 2 surge protection device (SPD) with remote signalling, designed to protect low-voltage electrical installations against transient overvoltages caused by lightning-induced disturbances and electrical switching operations. Part of the Finder 7P Series, this compact surge arrester uses metal oxide varistor technology to help protect electrical distribution systems, industrial control equipment and sensitive electronic components.
Designed for 400 V AC nominal electrical systems, the Finder 7P.21.8.440.1020 features a 440 V AC maximum continuous operating voltage (Uc), a 20 kA nominal discharge current (In) and a 40 kA maximum discharge current (Imax). Its 1.9 kV voltage protection level (Up) helps limit transient overvoltages reaching connected electrical equipment.
Unlike the 7P.21.8.440.0020 version, the 7P.21.8.440.1020 includes an integrated changeover contact for remote status signalling, together with the compatible Finder 07P.01 connector. Its replaceable varistor cartridge, visual protection status indication, compact 17.8 mm width and standard 35 mm DIN rail mounting make it suitable for industrial switchboards, commercial distribution boards and monitored electrical installations.
Key Advantages
- Type 2 surge protection against induced lightning overvoltages and electrical switching transients.
- Integrated remote signalling contact enables external monitoring of surge protection status.
- SPDT changeover contact provides flexible healthy/replacement status indication.
- Finder 07P.01 signalling connector included for convenient remote monitoring connections.
- 440 V AC maximum continuous operating voltage for compatible electrical distribution systems.
- 20 kA nominal discharge current provides substantial transient surge protection capability.
- 40 kA maximum discharge current supports protection against higher-energy surge events.
- 1.9 kV voltage protection level helps reduce transient voltage stress on downstream equipment.
- Replaceable varistor cartridge simplifies maintenance without replacing the complete SPD base.
- Visual protection status indication enables quick local inspection.
- Compact 17.8 mm modular width conserves valuable DIN rail space.
- 35 mm DIN rail mounting supports straightforward electrical panel installation.
- IP20 ingress protection for installation within suitable electrical enclosures.
- −40 to +80 °C operating temperature range supports demanding industrial environments.
Key Features
- Finder 7P Series surge protection device.
- 7P.21 single-pole surge arrester configuration.
- Type 2 SPD classification.
- Single-pole metal oxide varistor protection.
- 400 V AC nominal voltage.
- 440 V AC / 585 V DC maximum continuous operating voltage.
- 20 kA nominal discharge current (In), 8/20 µs waveform.
- 40 kA maximum discharge current (Imax), 8/20 µs waveform.
- 1.9 kV voltage protection level (Up).
- 25 kA short-circuit current rating (Isccr).
- Replaceable Finder 7P.20.8.440.0020 varistor cartridge.
- Optical status indication for functional or replacement condition.
- Integrated 1 CO (SPDT) remote signalling contact.
- Remote contact rating: 0.5 A at 250 V AC or 0.1 A at 30 V DC.
- Finder 07P.01 remote signalling connector included.
- IP20 ingress protection.
- −40 to +80 °C operating temperature.
- 35 mm DIN rail mounting according to EN 60715.
- 17.8 mm modular width.
- Screw terminal electrical connections.
Technical Specifications
- Manufacturer: Finder
- Series: 7P Series
- Product family: 7P.21
- Model: 7P.21.8.440.1020
- Product type: Surge protection device with remote signalling
- SPD classification: Type 2
- Number of poles: 1
- Protection technology: Metal oxide varistor (MOV)
- Nominal voltage (Un): 400 V AC
- Maximum continuous operating voltage (Uc): 440 V AC / 585 V DC
- Nominal discharge current (In), 8/20 µs: 20 kA
- Maximum discharge current (Imax), 8/20 µs: 40 kA
- Voltage protection level (Up): 1.9 kV
- Voltage protection level at 5 kA: 1.5 kV
- Short-circuit current rating (Isccr): 25 kA
- Maximum upstream backup fuse: 125 A, subject to installation requirements
- Protection module: Replaceable varistor cartridge
- Replacement cartridge: 7P.20.8.440.0020
- Local status indication: Visual healthy/replacement indicator
- Remote signalling: Integrated changeover contact
- Remote contact configuration: 1 CO (SPDT)
- Remote contact AC rating: 0.5 A at 250 V AC
- Remote contact DC rating: 0.1 A at 30 V DC
- Remote signalling connector: Finder 07P.01, included
- Remote signalling conductor cross-section: 1.5 mm²
- Operating temperature: −40 to +80 °C
- Ingress protection: IP20
- Mounting: 35 mm DIN rail
- Mounting standard: EN 60715
- Main terminal type: Screw terminals
- Solid conductor cross-section: 1–35 mm²
- Flexible conductor cross-section: 1–25 mm²
- Conductor stripping length: 12 mm
- Terminal tightening torque: 3 Nm
- Width: 17.8 mm
- Height: 82.8 mm
- Depth: 65.9 mm
- Net weight: Approximately 127 g
- Relevant standard: EN/IEC 61643-11
- EAN: 8012823394008
- Manufacturer part number: 7P.21.8.440.1020
Type 2 Varistor Protection for Industrial Electrical Systems
The Finder 7P.21.8.440.1020 uses metal oxide varistor technology to limit transient overvoltages in compatible low-voltage electrical installations. During normal operation, the varistor maintains high electrical resistance. When a transient surge raises the voltage beyond its operating threshold, the varistor becomes conductive and diverts surge current through the protective circuit.
Its 20 kA nominal discharge current and 40 kA maximum discharge current provide protection against induced lightning surges and switching disturbances. The 1.9 kV voltage protection level helps reduce voltage stress on downstream electrical equipment, including industrial controllers, power supplies and automation systems.
The device is suitable for installation at the boundary between lightning protection zones LPZ 1 and LPZ 2, or at other locations determined by an appropriate surge protection assessment. Correct SPD coordination, protective earthing, backup protection and connection conductor routing are essential to achieving the intended protection performance.
Integrated Remote Signalling and Replaceable Surge Protection Module
A key advantage of the Finder 7P.21.8.440.1020 is its integrated SPDT remote signalling contact. This contact allows the condition of the surge protection module to be monitored by compatible PLC inputs, building management systems, alarm circuits or maintenance monitoring equipment. It is particularly useful where the SPD is installed inside a cabinet that is not inspected frequently.
The remote signalling contact is rated at 0.5 A at 250 V AC or 0.1 A at 30 V DC. The supplied Finder 07P.01 connector supports connection to the monitoring circuit, while the front-mounted visual indicator provides immediate local confirmation of the varistor's condition.
The replaceable Finder 7P.20.8.440.0020 varistor cartridge enables maintenance personnel to renew the protective element when replacement is required, without removing the entire DIN rail-mounted SPD base. This helps simplify maintenance and reduce unnecessary replacement of electrical installation components.
Typical Applications
- Industrial electrical distribution boards.
- Three-phase 400 V AC electrical distribution systems.
- Commercial building switchboards.
- PLC and industrial automation control panels.
- Motor control centres and variable frequency drive installations.
- Manufacturing machinery electrical supplies.
- Building management systems requiring SPD status monitoring.
- Remote electrical infrastructure and unmanned installations.
- Electrical cabinets with centralised alarm or maintenance systems.
- HVAC and building services electrical distribution.
- Lighting infrastructure and outdoor electrical control cabinets.
- OEM switchgear and monitored electrical distribution assemblies.
