Alarm Module Leds; Alarm/Audio Interface - GE MDS Master Station Technical Manual

Part Number Description
Both versions of this module provide user connections for external alarm dry contacts and four
wire audio.
replacement; power must be removed from the system before removal or installation of
this device. Refer to Section 7.4 Replacing Modules for information on removal and in-
stallation.

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.
LED Name
ALARM MAJ.
ALARM MIN.
ACT A
ACT B

Alarm/Audio Interface

The ALARM/AUDIO Interface on the Alarm/Relay module provides audio signaling and alarm
outputs as shown below.
AUDIO:
4-wire audio circuits are connected to pins 1 through 4 as shown in Figure 9.
•
Terminals 1 and 2 are for transmit audio input with a nominal 600Ω impedance.
•
Terminals 3 and 4 provide receive audio output with a nominal 600 Ω impedance.
•
Pin 5 connects to an external keying source. Shorting pins 5 to pin 7 can key the radio
•
when PTT LOW is configured in software. When PTT is configured high in software,
pulling PTT to 3.3V keys the radio.
The interface is compatible with an external VOX adapter, although this product features an in-
tegrated VOX circuit with digital threshold control. For applications using the external VOX
adapter, 12VDC on pin 6 can be used to power the external module.
ALARMS:
88
Table 6-14. Alarm Modules
System
The Alarm or Alarm/Relay module does not support hot swappable field
Table 6-15. Alarm Module LEDs
Behavior
RED
RED
BLUE
BLUE
MDS™ Master Station
Interfaces and Indicators
Alarm/Audio Connector
Meaning
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
MDS 05-6399A01, Rev. E