Chapter 3. Installation
88
Dual CSU Interface
The Dual CSU Interface offers a T1 interface, or a DSX-1 interface, with special test
loopback capabilities between the T1 transmission line and the equipment. It is available
in three versions.
• P/N 30318-101 with interface T1 (T1-1) and DSX-1 (T1-2)
• P/N 30318-102 with two DSX-1 interfaces
• P/N 30318-103 with two T1 interfaces
The Line Build-Out (LBO) for T1, and/or equalizer for DSX-1 circuits, maintains correct
bipolar waveforms and levels on the transmit side. The T1 LBO settings are 0, -7.5, or -15
dB. The DSX-1 equalizer settings are 150 ft., 450 ft, or 750 ft.
Switch SW1 (T1-1) on Model 30318-101 allows the unit to be adjusted to the length of
cable between the Dual CSU Interface Unit and the next repeater. Switch SW2 (T1-2) is
used for equalizing the cable length to the local device termination.
Switches SW1 (T1-1) and SW2 (T1-2) on Model 30318-102 are used for equalizing the
cable lengths to local device terminations.
Switches SW1 (T1-1) and SW2 (T1-2) on Model 30318-103 allow the unit to be adjusted
to the length of cable between the Dual CSU Interface and the repeaters in both
directions.
Jumpers W1 and W2 on the main circuit board will either loop span power back toward
the span power source (when the jumpers are in the vertical position), or will bypass the
span power around the D/I Mux III (when the jumpers are in the default, or horizontal,
position).
WARNING!
Be sure to plug the Dual CSU Interface into its designated slot. Inadvertently plugging it into
other than its own slot will damage the unit.
Install the Dual CSU Interface unit by performing the following steps in the order given.
1. To set the LBO attenuator for the proper T1 level, first contact the local carrier for line
level requirements, then set the LBO switch accordingly, normally 0 dB. (Use -7.5 dB
when connecting a T1 LBO interface to a local PBX that is closer than 500 feet.)
2. To set the DSX-1 EQL attenuator for the proper DS1 level, first determine the length
of the connecting cable, then set the equalization switch accordingly.
3. To set jumpers W1 and W2 for span power loop mode (bypass mode is the default
set by the factory), use needlenose pliers to position jumpers W1 and W2 vertically
for LOOP mode. The span power will be looped back to the span power source.
Otherwise, jumpers W1 and W2 are positioned horizontally for BYPASS mode; the
span power will bypass the D/I Mux III.
4. Install the Dual CSU Interface.
To Next Page
Loading...
Need help?
General