DEHN DEHNflex DFL M 255 Type 2 Surge Arrester 2-Pole 280V AC 40kA IP20

Electrical surges and transient overvoltages can silently degrade or instantly destroy sensitive equipment in residential and commercial installations. The DEHN DEHNflex DFL M 255 Type 2 surge arrester provides a robust, space-saving solution to protect your electrical system from damage caused by indirect lightning strikes and switching operations. Engineered for DIN rail mounting, this 2-pole device offers reliable protection for single-phase 230 V AC systems, ensuring your appliances and electronics continue to operate safely.

Who is it for

This surge arrester is ideal for electricians, panel builders, and facility managers who need a dependable Type 2 surge protection device for distribution boards and sub-distribution panels. It is particularly suited for residential and commercial buildings where protection of sensitive loads such as computers, home automation systems, and industrial controls is required.

Main features

• Type 2 / Class II surge protection according to IEC 61643-11 and EN 61643-11
• High discharge capacity: nominal discharge current of 20 kA (8/20 µs) and maximum discharge current of 40 kA (8/20 µs)
• Low voltage protection level (Up) of ≤ 1.3 kV for effective protection of connected equipment
• Fast response time of less than 25 ns
• Visual status indication: green = operational, red = fault
• Compact design for 35 mm DIN rail mounting, only 2 modules wide
• Flame-retardant thermoplastic housing with IP20 protection
• Wide operating temperature range from -40 °C to +80 °C

Specifications

• Type of SPD: Type 2 / Class II
• Nominal Voltage (Un): 230 V AC (50/60 Hz)
• Maximum Continuous Operating Voltage (Uc): 280 V AC
• Nominal Discharge Current (In) (8/20 µs): 20 kA
• Maximum Discharge Current (Imax) (8/20 µs): 40 kA
• Voltage Protection Level (Up) at In: ≤ 1.3 kV
• Response Time (tA): < 25 ns
• Number of Poles: 2
• Protection Path: L-N, N-PE
• Mounting Type: 35 mm DIN rail
• Housing Material: Thermoplastic, flame-retardant
• Operating Temperature Range: -40 °C to +80 °C
• Ingress Protection (IP) Rating: IP20
• Standards Compliance: IEC 61643-11 / EN 61643-11
• Short-circuit withstand capability (Isccr): 25 kA (with max. backup fuse)
• Maximum Backup Fuse: 125 A gG
• Connection Terminals: Screw terminals
• Conductor Cross-section (solid): 1.5 - 35 mm²
• Conductor Cross-section (stranded): 1.5 - 25 mm²
• Status Indication: Visual (green = OK, red = fault)

Tips

Install the DEHNflex DFL M 255 close to the incoming supply or at the sub-distribution board to protect downstream equipment. Ensure proper earthing and follow local wiring regulations. Regularly check the visual status indicator to confirm the arrester is operational; replace it if the indicator turns red.