110 MDS™ Master Station MDS 05-6399A01, Rev. F
Table 6-19. 6847 Alarm Module RF Performance
The Alarm or Alarm/Relay module does not support hot swappable field
replacement; power must be removed from the system before removal or
installation of this device. Refer to Section 8.4 Replacing Modules for information on
removal and installation.
Alarm Module LEDs
The Alarm Module includes LEDs to indicate the active Radio Module (A or B) as well as the
presence of a Major or Minor Alarm.
Table 6-20. Alarm Module LEDs
On—Major Alarm (Master Station)
On—Minor Alarm (Master Station)
On—Radio A Active
Off—Radio A Standby
On—Radio B Active
Off—Radio B Standby
Alarm/Audio Interface
The ALARM/AUDIO Interface on the Alarm/Relay module provides audio signaling and alarm
outputs as shown below.
AUDIO (MPRS Only):
• 4-wire audio circuits are connected to pins 1 through 4 as shown in Figure 6-10.
• Terminals 1 and 2 are for transmit audio input with a nominal 600 impedance.
• Terminals 3 and 4 provide receive audio output with a nominal 600 impedance.