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Millennium SC_MAN
Rev 2.0
Table 33 Controller Alarm Descriptions
Alarm Description
Explanation
History Cleared
A user has cleared the event history record of one of MSC history reports. This is a latched
event, remaining active until cleared by a user.
High Float Voltage
Plant voltage is above the programmed threshold for this alarm. Set the HFV threshold
lower than the HV threshold which causes a HVSD signal to be issued to plant rectifiers.
High Voltage
Plant voltage is above the programmed threshold for this alarm. The HV alarm causes a
HVSD signal to be issued to plant rectifiers.
Low Current
A connected rectifier has load share enabled, but its present output load is less than a
predefined threshold for that rectifier type. (Usually 3% or less of capacity.)
Limited Recharge
The plant load has exceeded the programmed percentage of the total rectifier capacity set
for this alarm. Rectifier capacity may be inadequate for recharging batteries in an
acceptable period of time following an extended battery discharge. This is a latched event,
remaining active until cleared by a user.
Low Voltage Disconnect
An externally controlled LVD is open, providing a closure signal to MSC BSL
-
61/
-
62 for
alarm purposes.
Low Voltage Disconnect Fail
The monitoring circuit of an external LVD has failed, providing a resistive battery potential
signal into MSC BSL
-
84.
Manual Off
A connected rectifier has been manually turned off or has lost AC input power.
Major Comm Fail Alarm
The controller has lost communication with two or more devices that it had previously
recognized on its rectifier/converter/BIC serial bus. Typically indicates that the serial bus
is physically interrupted. If any of these devices is being permanently removed from
service, it is necessary to issue UNINSTALL DEVICES command to clear this alarm.
Module Failure
RPM system alarm. A module connected to the RPM serial bus has failed or has been
disconnected.
Multiple AC Fail
The controller has detected more than one AC failure from connected rectifiers. This is a
programmable threshold.
Multiple MAN Alarm
The controller has detected that more than one rectifier has manually been placed in
standby. This is a programmable threshold.
Multiple Rectifier Fail
The number of rectifiers currently processing a RFA alarm has exceeded the programmable
threshold for this alarm.
Measurement Out of Range
RPM system alarm. A channel measurement on a RPM is outside the DC voltage range
designed for that RPM type. Often indicates reversed polarity for measurement leads on a
unipolar module type.