Lucent DDM-2000 OC-3 User And Service Manual page 653

Tarp release 13 and later volume ii
Table of Contents

Advertisement

TAP-107
: Trouble Clearing
Page 9 of 28
Table B – RTRV-ALM Message Descriptions (Continued)
Description
forced switch
frequency error
holdover mode active
Alarm
Level
ABN
MJ
NE ACTY
DDM-2000 OC-3 M
Issue 2, February 2000
Meaning
When associated with an OC-3 line, this message
means that the identified line is not selected as the
active receiving line, and an automatic or manual
protection switch to make this the active receiving
line will not be done. The forced switch will remain
in effect until the protection switch is reset, or a
lockout or inhibit switch request is received.
Note: OC-3 line switching is unidirectional.
Because of this, the specified OC-3 line might still
be active (if the far end is selecting the specified
line to receive traffic), and the far end might still be
free to switch the line it is selecting to receive
traffic. (See the switch-line: command.)
When associated with a FUNCTION UNITS slot or
a LOW SPEED service slot, this message means
that the identified equipment is not active, and an
automatic or manual switch to make it active will
not be done. The forced switch will remain in effect
until the protection switch is reset, or a lockout or
inhibit switch request is received. (See the
switch-fn: and switch-ls: commands.)
This alarm condition indicates that an incoming
timing signal has an unacceptable frequency offset.
Likely causes: A DS1 external timing reference to
the local shelf or a remote shelf has a frequency
offset greater than about 20 hertz.
System is in holdover synchronization mode.
Likely causes: System was manually switched to
holdover mode (with switch-sync: command or
in a central office system, with TBOS control point
54) and switch has not been reset; or the system
automatically switched to holdover mode due to
failure of timing references, and either
(1) the reference failures have not cleared, or
(2) the system is provisioned for nonrevertive
synchronization mode switching, or
(3) the system is provisioned for External timing
and no external timing references are available, or
(4) the system is provisioned for loop-timed
operation and the optical line or OLIU circuit pack
has failed, or a message indicating an upstream
clock problem has been received on the sync
message bits of the optical line (rtrv-sync:
command) or
ULTIPLEXER
363-206-285

Advertisement

Table of Contents
loading

Table of Contents