DEHN DSH TN 255 Type 1+2 Combined Surge Arrester for Single-Phase TN Systems

This prewired combined lightning current and surge arrester delivers a total lightning impulse current of 25 kA (10/350 µs) and a voltage protection level of ≤1.5 kV, ensuring robust protection for low-voltage consumer installations in single-phase TN systems.

Advantages

Combines Type 1 and Type 2 protection in a single compact unit. No additional backup fuse is required up to 315 A (gG), simplifying installation and reducing costs. Optical green/red flag provides clear status indication. Energy coordination with downstream Type 3 arresters is guaranteed. Suitable for use in lightning protection zones 0–2.

Suitable for

• Single-phase TN-S and TN-C-S systems
• Main distribution boards and sub-distribution boards
• Protection of sensitive electronic equipment
• Installations requiring compliance with IEC 61643-11

Key specifications

• Nominal voltage: 230 V AC (50/60 Hz)
• Max continuous operating voltage: 255 V AC
• Lightning impulse current (10/350 µs): 12.5 kA per pole, 25 kA total
• Nominal discharge current (8/20 µs): 20 kA
• Max discharge current (8/20 µs): 50 kA
• Voltage protection level: ≤1.5 kV
• Follow current extinguishing capability: 100 A AC
• Response time: ≤100 ns
• Operating temperature: -40 °C to +80 °C
• Mounting: 35 mm DIN rail, width 2 modules (36 mm)
• Degree of protection: IP20
• Connection cross-section: 1.5–25 mm² solid / 1.5–16 mm² stranded

Recommendations

For optimal protection, install the DSH TN 255 at the service entrance and coordinate with downstream Type 3 arresters for sensitive equipment.