Section 150-232-100
Revision 01
Page 68
5.08 Figure 36 through Figure 38 show the ALARM HISTORY screens for Doubler applications. The alarms are
defined in Section A Paragraph 4.01. The LOS and PWR system alarms are common to all spans. Only the LOSW,
ES & MARGIN are span specific alarms. The PWR-OPEN and PWR-SHRT alarms indicate alarm conditions on the
HLU-232 List1D. PWR alarm conditions apply only to SPAN 1 eventhough they are displayed on the other spans. In
Figure 36 through Figure 38, the “First” & “Last” columns contain the time & date stamp of the first & last occurrence
of each alarm. The “Current” column shows the status of each alarm. The “Count” column lists the number of times
each alarm occurred. All the data can be cleared by pressing C (Clear). The maximum non-overflowing count is
999. The SPAN 1 Screen concerns alarms that occurred on the two HDSL loops between the HLU-232 List 1D and
the first Doubler (HDU1). The SPAN 2 Screen refers to the loops between the first Doubler (HDU1) and the HRU-
412 for one-Doubler circuits or between the first and second Doublers (HDU1 & HDU2) for two-Doubler circuits. The
SPAN 3 Screen refers to the loops between the second Doubler and the HRU-412 for two-Doubler circuits. The RS-
232 terminal interface at the HRU-412 does not allow the data to be cleared.
5.09 Selection “H” from the MAIN MENU Screen allows the Circuit ID# to be set. It is limited to 24 alphanumeric
characters. It, like the system settings, is stored in NVRAM and thus remains when power is lost. Note that the
Circuit ID# is not available at the HRU-412 Maintenance Port.
5.10 Selection I of the Protection Line Unit’s Main Menu (Figure 39) causes the Protection Switching Functions
Menu (Figure 40) to be displayed. From this menu, the Protection Mode, Minimum Hold-In Time, BER Threshold,
BER Interval, and Lock-In parameters can be set, as described in Section A, subsection 6. Select A to view the
Protection Mode Menu (Figure 41).
5.11 Selection J on the Protection Line Unit’s Main Menu (Figure 39) provides a switchover event history, (Figure
42) lists each Protection Switch event type, the date and time of both the oldest and the most recent event, along
with a total number of occurrences and reason for last switchover.
5.12 For Protection Switching applications, ESAL (Errored Seconds Alarm) should be disabled.
