Surge Arrester Simet B+C 4P 30 kA 275 V (model 85201010)

Simet B+C 4P surge arrester model 85201010 is a compact overvoltage protection device engineered for TN and TT systems with a nominal voltage of 275 V. The device combines Class B and Class C protection characteristics in a four-pole design to limit the effects of transient overvoltages and to divert surge energy to ground. It is intended for installation in residential and commercial distribution boards where coordinated protection with upstream devices is required to safeguard electrical equipment and wiring from lightning-induced and switching overvoltages.

Advantages

The Simet B+C 4P surge arrester provides coordinated two-stage protection by integrating B-class (primary) and C-class (secondary) performance in a single unit. Its four-pole configuration protects all phases and the neutral conductor, maintaining system continuity while reducing residual voltage levels. The device is designed for quick response to transient events, high discharge capability up to 30 kA, and straightforward DIN-rail mounting for fast installation in standard consumer and industrial panels.

Suitable for

• Residential distribution boards and apartment electrical panels
• Small and medium commercial buildings and retail premises
• Protection of sensitive electronic equipment such as HVAC controllers, IT devices, and security systems
• Coordinated use with upstream overcurrent or primary surge protection devices

Key specifications

• Nominal voltage: 275 V
• Poles: 4-pole configuration (three phases + neutral)
• Maximum discharge current: 30 kA (single impulse)
• Protection classes: Combined B and C characteristics for primary and secondary surge protection
• Mounting: DIN-rail compatible housing for distribution boards
• Application: Designed for TN and TT earthing systems

How to use

Install the surge arrester in the main or sub-distribution board on a standard DIN rail according to local electrical codes. Connect the phase and neutral conductors to the corresponding terminals and ensure a reliable equipotential bonding to the building ground/earth. Place the unit as close as practicable to the incoming service or the protected equipment to minimize lead length and residual voltage. Verify that upstream protective devices and earthing systems are compatible and that the coordinated protection scheme is maintained.

Usage recommendations

Use this surge arrester as part of a coordinated protection system: combine a primary device for high-energy impulses with the Simet B+C unit for downstream protection. Periodically inspect the device for status indicators or signs of damage after major surge events and follow the manufacturer’s replacement guidelines if the internal protective elements have operated.