Signaling Device Interface Modules

Signaling Device Interface Modules

Product Description

FLM‑420‑NAC Signaling Device Interface Modules make it possible to monitor and activate a group of signaling devices (NAC = Notification Appliance Circuit) in the Local Security Network LSN. Each interface module offers one monitored primary line. This means one signaling device line can be connected to LSN fire panels. The following can be connected: • Sounders • Strobes • Horns.


  • Rotary switches for automatic or manual address setting
  • Control of signaling device line by pole reversal
  • Synchronized activation of all signaling devices connected to a LSN module via FLM‑420‑NAC Signaling Device Interface Module
  • Ten different output signals via LSN selectable
  • Maintains LSN loop functions in the event of wire interruption or short-circuit thanks to two integrated isolators
  • Available with surface-mounted housing or DIN rail adapter


Input voltage

15 V DC to 33 V DC

from LSN

6,06 mA (normal operation and alarm)

from external power supply

15 mA (normal operation) + output current

External power supply

20,4 V DC to 29 V DC

Max. output current

3 A (during an alarm, from ext. power supply)

EOL resistance

3.9 kΩ



Green LED

Normal operation

LSN/Address setting

3 rotary switches for

Mode LSN "classic" or LSN improved version