Surge Arrestor 80kA, 2-4 Pole, 385V | Onesto SPD

The Onesto BY7-80 Surge Protection Device is a Class II (Type 2) surge arrestor rated at 80kA, designed to protect electrical installations, distribution boards and connected equipment from transient overvoltage caused by lightning strikes and switching surges. It is suitable for commercial and industrial TN and TT power supply networks with a higher lightning exposure risk, and offers a visual pass/fail status indicator so installers and maintenance teams can check protection status at a glance. Available in 2, 3 and 4 pole configurations at 385V, it is a high-capacity choice for main incoming boards where a strong first line of surge defence is required.

• Application: Suitable for main incoming board surge protection on TN/TT networks with higher lightning exposure, 385V
• Key specification: 80kA maximum discharge current (Imax), Class II / Type 2 SPD
• Configuration: Available in 2, 3 and 4 pole versions
• Status indicator: Green/red indication window shows functional or failed status
• Mounting: 35mm DIN rail, IP20 enclosure

Key Features

• 80kA maximum discharge current (8/20µs) provides a high level of protection for main boards in high-lightning-risk areas
• Visual green (functional) / red (failed) indication window means the device can be checked without removing it from the DIN rail
• PA66 UL94-V0 flame-retardant housing suited to enclosure and distribution board installation
• Compact DIN rail mounting saves space in crowded distribution boards
• Suitable for TN and TT earthing systems

Typical Applications

• Main incoming distribution board protection for commercial and industrial sites
• Farms, rural properties and elevated structures with high lightning exposure
• Protection ahead of downstream 10-40kA SPDs as part of a coordinated (cascaded) surge protection scheme
• Protection of sensitive electronic and control equipment against transient overvoltage
• Commercial and light industrial installations exposed to switching surges

Technical Specifications

What's Included

• 1 x Onesto BY7-80 Surge Protection Device (pole configuration as selected)

Please note: DIN rail, distribution board wiring, circuit breakers and installation accessories are not included unless specifically listed above.

Installation & Compatibility Notes

• Confirm your board's earthing system (TN or TT) before ordering — this range is supplied at 385V.
• Select the pole configuration (2P, 3P or 4P) that matches your distribution board and phase configuration.
• Installation should be carried out by a suitably qualified electrician in line with local wiring regulations.
• Check the status indicator periodically — a red window means the SPD has operated and must be replaced.

Warranty & Support

This product is supplied with the applicable manufacturer or supplier warranty, subject to correct installation, correct application, and warranty terms.

Zisabo supplies quality plumbing, pump, filtration and electrical products with practical support to help customers choose the correct item for their application. If you are unsure whether this product is suitable, contact us before ordering and our team will assist where possible.

Need help choosing? If you are unsure whether this product is suitable for your board, contact Zisabo with your system voltage, earthing type and pole configuration, and we will assist where possible.