GE Industrial Solutions Galaxy Vector Controller GCM3 - Manual (Page 35)

Galaxy Vector Controller GCM2, GCM3
Issue 4 January 2008 Operation 3 - 1
3 Operation
Office Alarm
Contacts
The basic Galaxy VC issues PMJ, PMN, MJF, BD, ACF and
HV/2ACF/VLV office alarms off the BLJ3 and BTJ2/BTJ3
boards. Refer to Table 2-G and 2-N, respectively, for a
description of their output terminals. Refer to Table 3-A for a
listing of the various available alarms. Refer to Table 3-B for a
listing of alarm relays and their associated front panel LEDs.
Alarm
Descriptions
To see active alarms, press the Active Alarm softkey, then use
the
∧ or ∨ keys to page through alarms. See Tables 3-A and 3-B.
The alarms are listed in order of severity. Some abbreviations are
required to fit the LCD screen.
Very Low Voltage Alarms and Battery on Discharge
When rectifier output is insufficient to maintain the load current
at the set voltage (typically because of an ac power failure), the
plant bus voltage drops. When this voltage drops below the
battery voltage, the batteries start providing current to the load.
Any time that the plant voltage is below the threshold selected
for BD, the Battery on Discharge alarm activates. If the plant
voltage continues to drop, a second, lower threshold can be
reached, activating a Very Low Voltage alarm. Default values
for these thresholds are set at the factory. These thresholds can
be changed by the operator in the configuration menu as
described in the Installation and Configuration section of this
manual (Section 4). S1.5 set to “1” will allow the relay dedicated
for HV/ACF/VLV, K8, to be asserted for the VLV condition.
Note that a BD alarm does not necessarily mean that the batteries
are discharging, only that the present voltage is lower than the
set point for this alarm. This alarm may be activated by an
incorrectly set BD threshold or plant voltage set point.