Installation must only be performed by authorized and specialized personnel!
Electrostatic discharge (ESD)! Electronic components could become damaged.
Ground yourself using a wrist strap or take other suitable actions.
Live components and stripped cable! Risk of injury from electric shock.
The system must be current-free during connection work.
FLM-420-NAC Signaling Device Interface Modules make it possible to connect sounder, strobes, and horns to LSN
fire panels. Each interface offers one monitored primary line. The control of the signaling device line
(NAC=Notification Appliance Circuit) is performed through polarity reversal.
Interface module variants:
FLM-420-NAC-S for surface-mounting with housing (see Figure 2 to Figure 6, Page 5 to Page 8).
FLM-420-NAC-D for installation on a DIN rail with adapter (see Figure 7 and Figure 8, Page 9 to 10).
Fit a rotary switch in the required position using a pan head slotted screwdriver (see Figure 1, Page 4).
0 0 0
Loop/stub in LSN improved version mode with automatic addressing (T-tap system not possible)
0 0 1 — 2 5 4
Loop/stub/T-tap system in LSN improved version mode with manual addressing
CL 0 0
Loop/stub in LSN classic mode
2 5 5 — 2 9 9
Non-permitted address range (error message on fire panel)!
IN: b | a
OUT: b | a
0 V | 24 V
LSN: a1- | b1+ | a2- | b2+ LSN in / LSN out
FAIL ac | FAIL bat
Max. current consumption from LSN
Max. current consumption from ext. power supply
Ext. power supply
Max. output current
Classes of equipment as per IEC 60950
Protection class as per IEC 60529
Permitted operating / storage temperature
Permitted relative humidity
Material interface module housing
Material surface-mount housing
F.01U.003.284 | 6.0 | 2010.06
NAC zone input
NAC zone output
Ext. power supply
Fault ext. voltage / Fault ext. battery
- Stub: see Figure 9, Page 11
- Loop: see Figure 10, Page 11
2 LEDs (red = alarm, green = normal operation)
15 V DC — 33 V DC
6,06 mA (standby/during an alarm)
15 mA (standby) + output current
20,4 V DC — 29 V DC
3 A (during an alarm, from ext. power supply)
Class III equipment
FLM-420-NAC-S: IP 54
FLM-420-NAC-D: IP 30
-20 °C bis +50 °C / -25 °C bis +85 °C
< 96%, non-condensing
ABS + PC-Blend
FLM-420-NAC-S | FLM-420-NAC-D
Bosch Sicherheitssysteme GmbH