Csu Front-Panel Controls - AT&T MERLIN LEGEND Installation & Maintenance Manual

Installation
Table 3-17 Continued
LED
System Side
LOOPED
FRAME
LOSS
LOW DENS
ACO
Table 3-18 CSU Front-Panel Controls
Control
LOOPBACK
SENDCODE
ACO
3-36 Channel Service Unit
Color
Yellow Loopback activated on
system side
Red Loss of signal, loss of frame
synch, improper frame
sequence, or unframed
signal
Red Avg. ones density below
threshold or consecutive
zeroes threshold
Yellow Lights when ACO button is
pressed when ALARM LED
is lit
Loops the incoming signal from the system
to the system
Sends "loop up" or "loop down" code to far-
end CSU
Functions only when the ALARM LED is lit
turns on ACO LED and deactivates audible
alarm; clears alarm if the alarm condition has
been cleared
When Lit Indicates
Function