Integrators' Reference Manual for For ViewStation EX, ViewStation FX, and VS4000

Chapter 2 - Technical Information
© Polycom, Inc. 27
Indicators on the PRI Network Interface Module
The tables below describe the expected behavior of the indicator
lamps on the PRI network interface module. On the network side,
the expected behavior depends on whether it is a T1 module or an
E1 module.
Non-Facility
Associated Signaling
(NFAS)
Not supported
Special services
(Caller ID, call
blocking, etc.)
Not supported
Table 2-17. PRI Network Side Indicator Lamps
Indication PRI T1 PRI E1
Red LED blinking Not connected to the network, or no power to the
upstream equipment
Red LED on Connected to the network, but no clock sync
Yellow LED blinking Receiving clock and
frame sync; receiving
RAI from the network
with CRC errors
Yellow LED on Receiving clock and
frame sync, waiting for
a timer to elapse
Receiving clock and
frame sync; receiving
Remote Alarm
Indication (RAI) from
the network with no
Cyclic Redundancy
Check (CRC) errors
Red and yellow
LEDs on
Receiving clock sync;
receiving AIS Alarm
Indication Signal
(unframed all-ones)
Green LED on Synchronized with the network and ready to use
Table 2-16. PRI T1 and E1 Network Interface Modules (Continued)
Parameter PRI T1 PRI E1