31
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4.0 INSTALLATION
The Model 2720 is equipped with DTE, network, and power inter-
faces. This section briefly describes connection to each.
4.1 DTE INTERFACE CONNECTION
The DTE interface is a V.35 DCE presented as an M/34 male con-
nector. This interface is designed to plug directly into a DTE interface
(See Appendix D for V.35 interface pin assignments).
4.2 NETWORK INTERFACE CONNECTION
The Network Line Interface is an eight position keyed modular jack
configured as a RJ-48C. This interface will need to be configured to
match the line parameters (i.e. framing, line coding, etc.) supplied by
the central office.
4.3 DC POWER SUPPLY
The 36-60 VDC DC to DC adapter is supplied with the DC version of
the Model 2720. The black and red leads plug into a DC source (nomi-
nal 48VDC) and the barrel power connector plugs into the barrel power
supply jack on the 2720.
5.0 OPERATION
Once the NetLink-T1™ is installed and configured properly it is
ready to place into operation. This section describes the function of
the LED indicators, and the use of the loopback and pattern test
modes.
5.1 LED DESCRIPTIONS
The NetLink-T1™ is equipped with six LED indicators that monitor
the status of communication. Figure 12 (below) shows the location of
the LEDs on the NetLink-T1™ Series front panel.
T1 Link
Solid green indicates that the end to end TI
link is up. Signifying that the link is active.
The TI link LED is off when the link is down
TD
When the unit sends a one, the TD LED is
green. When it sends a zero, the TD LED is
orange. Moreover, the TD LED is active
only in active DS0 channels. In inactive
channels, the TD LED is off.
RD
When the unit receives a one, the RD LED
is green. When it receives a zero, the RD
LED is orange. Moreover, the RD LED is
active only in active DS0 channels. In inac-
tive channels, the RD LED is off.
ALM
The alarm LED indicates the presence of a
Blue or Yellow Alarm, or Out of Frame con-
dition. The ALM LED will blink on every half-
second. Alarms may occur due to:
• Loss of Synchronization
• Loss of Frame
• AIS (Blue Alarm)
• RAI (Yellow Alarm)
Figure 2. Model 2720 twisted pair line interface.
1 RX Data (TIP)
2 RX Data (RING)
3 (no connection)
4 TX Data (TIP)
5 TX Data (RING)
6 (no connection)
7 (no connection)
8 (no connection)
1
2
3
4
5
6
7
8
NOTE:
If the Model 2720 is being used for private short range
modem applications, the twisted pair cable connected to
its port will need to be a crossover cable. See Appendix
D for Interface pin assignments.
}
From Network
}
To network
To Power
Supply Jack
To -48VDC
Source
-Vin
+Vin
SWITCHING POWER SUPPL
Y
MODEL
: SYD1
106-0505
INPUT
: 36-60V 0.2A
MAX
OUTPUT
: +5V 1.0A
OUTPUT
POWER : 5W MAX
S/N
: G01234567890
MADE IN CHINA
BY
SUNNY
Black lead (-V)
Red lead (+V)
Barrel power connector
Figure 3: 2720/C Front Panel
