DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126 Issue 4
June 1999
Maintenance Object Repair Procedures
9-983MAINT (EPN Maintenance Circuit Pack)
9
9
MAINT (EPN Maintenance Circuit
Pack)
The TN775B EPN Maintenance circuit pack monitors and supports environmental
maintenance for EPN multicarrier or single-c arrier cabinets. The EPN
Maintenance circuit p ack provides switch softwa re with a mechanism to activate
or deactivate Emergency Transfer in the EPN. Control by the system of
Emergency Transfer can be overridden b y the Emergency Transfer Switch on the
faceplate of the circ uit pack. The EPN Maintenance circuit p ack invokes
Emergency Transfer when the EPN loses contact with the PPN or when the EPN
Maintenance circuit p ack loses contact with all Exp ansion Interface circuit p acks.
The EPN Maintenance circuit pack hand les loss of AC power in the EPN
multicarrier cabinet b y supplying batter y power for 15 seconds to the EPN
cabinet and then an ad ditional 10 minutes of power to just the c ontrol carrier in
the EPN. When power fails in a single-carrier EPN cabinet, no such p ower
holdover is available. In the event that an Exp ansion Interface circuit p ack goes
insane and is reset six times within 15 minutes, the EPN Maintenance ci rcuit pack
will hold the Expansion Links reset preventing the Expansion Interface circ uit
pack from running.
The EPN Maintenance circuit pack has alarm LED s whic h indicate the presence
of Major, Minor, and Warning alarms. A flashing LED indicates the presence of
an alarm within the cabinet. A c ontinuously lit LED indicates the presenc e of an
alarm elsewhere in the system.
A management terminal (G3-MT) can be directly connected to the TN775B EPN
Maintenance circuit p ack. This link operates at 9600 baud , but system software
throttles the rate of data flow to the TN775B for displa y on the G3-MT to about
1200 baud. All system com mands can be exec uted via the EPN G3-MT login.
However, due to the slow speed at which the EPN login operates, it is
recommended that it b e used only for maintenance sessions and not for system
administration.
The PPN communicates with the EPN Maintenance circuit pac k via the following
path; uplink messages from the EPN Maintenance c ircuit pack to the PPN take
exactly the reverse path. Messag es flow from the UN331B Processor circuit pac k
in the SPE to the TN1655 Packet Interface circuit pack, over th e Lan Bus to the
Active PPN Expansion Interface circuit p ack, across the fiber link to the Active
EPN Expansion Interface circuit pac k, and over a serial link to the EPN
Maintenance circuit p ack.
MO Name (in
Alarm Log) Alarm
Level Initial Command to
Run Full Name of MO
MAINT MINOR test maintenance sh EPN Maintenance Circuit Pack
MAINT MAJOR test maintenance l EPN Maintenance Circuit Pack