Operating instructions

28 Operating Instructions
2.6 Alarm Messages
The static switch monitoring system detects and annunciates a comprehensive set of alarm condi-
tions. Alarm messages are displayed on the Monitor/Mimic screen below the Output box. Alarm
messages remain active until the alarm condition has been corrected and the Alarm Reset switch
has been pushed. All active alarms are displayed on the Present Status screen. A record of the
last 128 alarms is stored in nonvolatile memory and can be viewed from the Event History
screens.
Upon occurrence of designated major alarms, the History Status buffer is frozen capturing the
Present Status screens before and after the alarm condition. When the History Status buffer is
frozen, the History Stored message is displayed above the Output box on the Monitor/Mimic
screen. When the History Stored message is displayed, qualified service personnel should view
the contents of the History Status buffer, investigate the cause of the alarm as soon as practical,
and reset the buffer to allow it to capture future alarm events. The History Status buffer is reset
by pressing and holding the Alarm Reset switch for five (5) seconds.
The Peak I1 OVLD and Peak I2 OVLD alarms inhibit automatic transfer due to an overload or
load fault. These alarms can be set for auto or manual transfer inhibit reset. In the auto reset
mode, transfer inhibit is reset as soon as the load current returns to normal. In the manual reset
mode, the Security Access Interlock must be activated to reset the transfer inhibit. In either
mode, the alarm message is latched and must be reset after the alarm condition has been cleared.
The cause of Peak I1 OVLD or Peak I2 OVLD needs to be investigated and resolved (such as by
reducing the overload condition or clearing the output fault) before returning the switch to normal
operation.
A shorted or open SCR alarm latches and automatically trips open a source input breaker (CB1 or
CB2) to prevent transfers in the event of an SCR failure. The SCR failure must be investigated
and repaired before returning the switch to normal operation. Both source input breakers must be
opened (such as when the unit is placed in maintenance bypass for servicing) before a shorted or
open SCR alarm can be reset.
When the system is furnished with an optional modem and a telephone line is connected to the
modem, the system can be programmed to automatically dial out upon occurrence of any of cer-
tain designated alarms. The auto-dial settings are accessed from the System Configuration
screen. For more information on the auto-dial feature, see the 2.7 - Communication Interfaces.
Table 1 lists available alarm messages, a description of the alarm, and any special functions acti-
vated with the alarm. The special functions are indicated as follows:
F—The indicated alarm Freezes the History Status buffer.
L—The indicated alarm Latches. A latched alarm remains displayed until the alarm condi-
tion has been corrected and the Alarm Reset switch has been pushed.
D—The indicated alarm initiates the Auto-Dial sequence through the optional modem.
A—The indicated alarm activates the Audible alarm