GE Grid Solutions MDS Master Station, Техническое руководство

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MDS 05-6399A01, Rev. F
MDS™ Master Station
111
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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
integrated 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
:
•
Terminals 8 and 9 provide solid state relay contacts that close when a minor alarm is
detected.
•
Terminals 10 and 11 provide relay contacts that close when a major alarm is detected. You
can redefine these relay contacts using the radio’s software (switched from minor to major
alarm outputs, or vice versa). The contacts are rated for non-inductive loads up to a
maximum 60 Volts (AC or DC) at 1 A.
Analog RSSI (MPRS Only)
:
When enabled in software, an RSSI voltage of 0 to 3V corresponding to -120 to -70dBm is
present on this line.
+12v 6 12 Analog RSSI
PTT 5 11 Major Alarm Contact
Rx Audio - 4 10 Major Alarm Contact
Rx Audio + 3 9 Minor Alarm Contact
Tx Audio - 2 8 Minor Alarm Contact
Tx Audio + 1 7 Ground
Figure 6-10: Alarm/Audio Connections
(As viewed from outside the radio)
Alarm/Relay Toggle Switch (6847 Only)
For redundant units, the Alarm/Relay module includes a manual override toggle switch, which
can be set into one of three positions to associate it with a particular radio. The toggle switch is
locking, and must be pulled out to change positions. Switch functions are as follows:
- Up
— Radio A
- Down
— Radio B
- Center — Automatic.
When the switch is set to Automatic, the active radio is determined by radio module presence
and alarm status.
If only one radio module is installed (A or B) it is recommended that
the switch be set to A or B, as appropriate.
The non-redundant version of the Alarm Module does not include the Toggle Switch.
Alarm/Relay RF Connections (6847 Only)
For redundant systems, the Alarm/Relay module includes a RF Connections for both the A and B
Radio Module, and RF OUT. These are all Dual FAKRA-SMB connectors. RF OUT is switched
between Radio A and Radio B depending on the currently active radio. RF OUT is normally
cabled to the Duplexer tray faceplate, even on systems that do not include a duplexer. Redundant
systems come from the factory already properly cabled between the Radio Modules,
Alarm/Relay Module and Duplexer tray faceplate. Connectors are keyed to ensure proper
orientation.
Non-redundant systems using the 6848 Alarm Module do not include RF Connections.