Avaya Definity SI Maintenance Manual page 65

Power
Table 2-2. Response to Power Service Interruption with an Internal Holdover Battery
System and
Configuration
Standard
High, Critical
Standard/High, Critical
1
Standard/High, Critical
Standard/High, Critical
1 The holdover times listed are in effect if the EPN contains a TN775 maintenance circuit pack.
However, if the EPN contains a TN775B maintenance circuit pack, the holdover time for the entire
cabinet is 10 seconds, and the holdover time for the control carrier is 10 minutes.
Table 2-3. Types of Cabinet Power Interruption
Shorter Holdover
System and Than Entire
Cabinet
PPN SCC No calls dropped
EPN SCC No calls dropped
NOTE:
When EPN power is interrupted for greater than the cabinet holdover but
less than the control carrier holdover, calls in the control carrier are held for
the duration of the interruption but are dropped when power is restored.
Single-Carrier Cabinets
In single-carrier cabinets, there is no internal AC wiring or distribution and no
software interaction with the power system. The power supplies themselves take
about 250 milliseconds for the voltages to drop below limits.
The control cabinet that houses the Switch Processing Element (SPE) is the only
cabinet that has an internal battery reserve. All other control cabinets and port
cabinets have the 250 millisecond power supply decay delay, after which all
connections and links associated with the cabinets are dropped.
555-233-123
Cabinet
PPNMCC
PPNMCC
PPN SCC/ESCC
EPN MCC
EPN SCC/ESCC
Longer Holdover than
Entire Cabinet, Shorter
Holdover than Control
Cabinet
All calls dropped
All calls dropped
Holdover for Holdover for Entire
Entire Cabinet Control Carrier (in
(in seconds)
10
10
1/4
15
1/4
Longer Holdover
Than Control
Carrier
System reloads
System reloads
Issue 4 May 2002
minutes)
10
5
2
none
none
Carrier
2-3