a/b Switching Module

Article number 90638

Switching module for controlling door bell, door opener and light systems using the 2-core a/b line, for TFS-Dialog 200/300/400 and TFS Universal plus.


  • Six a/b Switching Modules suitable for use with TFS-Dialog 200/300/400 or TFS-Universal plus, requiring only a two-core cable
  • Each button can control one or more switching modules, user programmable
a/b Switching Module
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If you want to switch on lights when a (doorbell) key is pressed, control your existing door bell, or inform your intrusion detection system about visitors at the door, then you need additional switch contacts.


As an exclusive connection option, you may use a/b Switching Modules which can easily be switched to any location on the signal line between the door terminal system and PBX, and initiate the switching operation when a key is pressed.


Features & technical data

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Technical Highlights
Dimensions Height (mm) 35 / Width (mm) 45 / Depth (mm) 10
Operating voltage via door bell transformer (alternating current) Voltage minimum 8 / Voltage (maximum) 18
Weight (g) 30
Contact load capacity (direct current) Voltage 40 / Current 1
Contact load capacity (alternating current) Voltage 18 / Current 1
Range (approx.) Range (m) 200
Switching frequency, 6 channels, 20–50 kHz, 100 MV Switching frequency 1 / 6 channels in the range 20 - 50 kHz, 100 mV
Delivery scope
  • a/b Switching module
  • Resistance (for activation of an electronic gong)

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