Surge Arrester

Surge arrester for KNX / EIB buses with connection wires.
  • Surge arrester for KNX / EIB buses
  • Extremely space-saving due to KNX / EIB bus terminal design
  • System-tested with EIBA certification


The discharge capacity, protective effect and mechanical design of BUStector surge arresters are adapted to the installation environment of KNX / EIB buses. Like a bus terminal, they can be plugged onto the bus terminal pins of a terminal device and can be connected by means of the existing connecting cables. BUStector surge arresters can also be connected to an existing bus terminal on the terminal device. They particularly protect line and area couplers as well as gateways and sensors installed at the outer walls of buildings.

Detail 1

Protection of a KNX power supply unit by means of a BUStector surge arrester mounted in the standard bus terminal slot.

Detail 2

Protection of a KNX bus coupling unit by means of a BUStector surge arrester mounted on a bus terminal in the mounting panel of a cable duct.




Basic circuit diagram BTDimension drawing BT

Surge arrester with KNX bus terminal design, adapted to the immunity of KNX / EIB systems. EIBA-certified.


Part No.
SPD class
Nominal voltage (Un)
Max. continuous operating voltage (d.c.) (UC)
Nominal current (IL)
D1 Lightning impulse current (10/350 µs) per line
C2 Nominal discharge current per line (In)
Voltage protection level line-line for In C2
Voltage protection level line-PG for In C2
Voltage protection level line-line at 1 kV/µs C3
Voltage protection level line-PG at 1 kV/µs C3
Cut-off frequency line-line (fG)
Capacitance line-line
Capacitance line-PG
Operating temperature range (TU)
Degree of protection
Earthing via
Enclosure material
Test standards
Part No.
  • BT 24
  • 925 001
  • B
  • 24 V
  • 45 V
  • 6 A
  • 1 kA
  • 5 kA
  • ≤ 1200 V
  • ≤ 650 V
  • ≤ 750 V
  • ≤ 500 V
  • 70 MHz
  • ≤ 10 pF
  • ≤ 10 pF
  • -40 °C ... +80 °C
  • IP 20
  • spring contacts (Ø1 mm) / connecting leads (Ø0.8 mm)
  • lead (0.75 mm2), 200 mm long
  • thermoplastic
  • blue
  • IEC 61643-21
  • EIBA certification No. Z 32/1399/95, EAC
  • 10 g
  • 4013364047365
  • 1 pc(s)
  • 925 001
  • Specifications (PDF)
  • More