DEHNbloc® modular

DB M 1 255 FM (961 125)

■ Coordinated spark-gap-based lightning current arrester consisting of a base part and a plug-in protection module

■ Maximum system availability due to RADAX Flow follow current limitation

■ Without additional cable length directly coordinated with DEHNguard surge protective device

Coordinated and modular single-pole lightning current arrester with high follow current limitation; with remote signalling contact for the monitoring system (floating changeover contact).

• SPD according to EN 61643-11 / IEC 61643-11 type 1 / class I 

• Nominal voltage (a.c.) (UN) 230 V (50 / 60 Hz) 

• Max. continuous operating voltage (a.c.) (UC) 255 V (50 / 60 Hz) 

• Lightning impulse current (10/350 µs) (Iimp) 50 kA

• Specific energy (W/R) 625.00 kJ/ohms 

• Voltage protection level (UP) ≤ 2.5 kV

• Follow current extinguishing capability (a.c.) (Ifi) 50 kArms

• Follow current limitation / Selectivity

• no tripping of a 32 A gG fuse up to 50 kArms (prosp.) 

• Response time (tA) ≤ 100 ns

• Max. backup fuse (L) up to IK = 50 kArms (ta ≤ 0.2 s) 500 A gG

• Max. backup fuse (L) up to IK = 50 kArms (ta ≤ 5 s) 315 A gG

• Max. backup fuse (L-L') 125 A gG

• Temporary overvoltage (TOV) (UT) – Characteristic 440 V / 120 min. – withstand 

• Operating temperature range (parallel connection) (TUP) -40 °C ... +80 °C 

• Operating temperature range (series connection) (TUS) -40 °C ... +60 °C 

• Operating state / fault indication green / red 

• Number of ports 1 

• Cross-sectional area (L/N, L'/N', N/PE (N)) (min.) 10 sq-mm. solid / flexible 

• Cross-sectional area (L/N, N/PE(N)) (max.) 50 sq-mm.

• Cross-sectional area (L'/N') (max.) 35 sq-mm.

• 2 stranded / 25 sq-mm flexible 

• For mounting on 35 mm DIN rails acc. to EN 60715 

• Enclosure material thermoplastic, red, UL 94 V-0 

• Place of installation indoor installation 

• Degree of protection IP 20 

• Capacity 2 module(s), DIN 43880

• Approvals VDE, KEMA, UL 

• Type of remote signalling contact changeover contact 

• Switching capacity (a.c.) 250 V / 0.5 A 

• Switching capacity (d.c.) 250 V / 0.1 A; 125 V / 0.2 A; 75 V / 0.5 A 

• Cross-sectional area for remote signalling terminals max. 1.5 sq-mm. solid / flexible 

• Use in switchgear installations with prospective short-circuit

• Max. prospective short-circuit current 100 kArms (220 kApeak)

• Limitation / Extinction of mains follow currents up to 100 kArms (220 kApeak)

• Max. backup fuse (L) up to IK = 100 kArms (ta ≤ 0.2 s) 500 A gG

• Max. backup fuse (L) up to IK = 100 kArms (ta ≤ 5 s) 315 A gG

• Nominal discharge current (8/20 µs) (In) 50 kA