
60 KENR8601
Systems Operation Section
AL16 Incorrect Phase Sequence – This fault
occurs whenever any synchronization function
is in progress, and the GSC+P verifies that the
generator and the bus have a phase sequence
mismatch. The incorrect Phase Sequence alarm is
immediately made active, and synchronization is
halted. In this case, the alarm is latched until the
synchronization request is removed. If t he request
was m ade locally using the SMS, then the SMS
mustbemovedtotheOFFpositiontoCLEARthe
alarm. If the phase sequence mismatch is detected
immediately following closure to a dead bus, but no
synchronization function is in progress, the “Incorrect
Phase S equence” alarm is made active but is not
latched. In this case, if the phase sequence mismatch
condition is not present, the alarm will be removed.
AL17 Improper Generator Or Bus Voltage – This
fault occurs whenever the generator voltage, bus
voltage, or both are incorrect for synchronization. The
alarm is generated only if synchronization is enabled
and synchronization request has been made. The
conditions that may cause an “Improper Generator
Alarm” or “Bus Voltage Alarm” are listed below.
•
The Bus voltage is too low f or synchronization .
•
The Generator voltage is too low for
synchronization.
•
The Generator voltage and the Bus voltage are
out of tolerance.
The specific conditions tested depend on the
synchronization request a nd on setpoint values.
Setpoint P303 enables or disables generator
voltage or bus voltage checking during automatic
synchronization. Setpoint P304 determines the
mazimum acceptable difference in voltage between
the bus voltage and the generator voltage.
This alarm will prevent frequency control and a nd
breaker closure while the alarm is active, but will
not halt synchronization. If the condition causing
the alarm is removed while synchro nization is in
progress, then the alarm will be removed and the
GSC+P w ill proceed with synchro niz at ion.
If the Improper Generator Alarm or the Bus Voltage
Alarm is active when synchronizationis halted due to
a synchronizer Time-ou t Alarm, the alarm is latched
until the synchron ization reque s t is removed. In this
case, if the request was made locally using the SMS,
then the SMS must be moved to the OFF position to
CLEAR the alarm. If the request was made remotely
using a Customer Communication Module (CCM),
then the CCM must send a Generator Synchronizer
Control command (with a value of OFF) to CLEAR
the alarm.
AL18 Synchronizer Time-out Alarm – This fault
occurs whenever the GSC+P is unable to complete
Automatic Synchronization or Dead Bus Parallel after
a progr ammed am ount of time. Fo r the purposes of
this alarm, Automatic Synchronization /Dead Bus
Parallel is considered complete after breaker closure
has been verified.
This alarm has two time-out thresholds,
Synchronization Time Warning and Maximum
Synchonization Time fault. Synchronization may be
halted, depending on the time-out threshold that has
been exceeded.
Timing for this alarm is started when Automatic
Synchronization is requested, and the Dead Bus
On-Time Delay (if the bus is dead) has completed.
Note: If the GSC+P closes the breaker, and a fault
occurs tha t causes the breaker to open within 1 5
seconds, the GSC+P will lock out all synchronization
functions until the SMS is turned to another position.
If the breaker opens after 15 seconds, the GSC+P
will reattempt the requested synchronization function.
Synchronization Time Warning
If the GSC+P is unable to complete Automatic
Synchronization or Dead Bus Paralleling during
thetimespecified in the Synchronization Time
Warning setpoint, the GSC+P will activate the
AL18 Synchronizer Time-out Alarm b ut continue
synchronization. If synchronization is completed
before the Maximum Synchronization Time fault
setpoint has expired, the alarm will be deactivated.
Maximum Synchronization Time Fault
If the GSC+P is unable to complete Automatic
Synchronization or Dead Bus Parallel during the
time specified in the Maximum Synchronization
Time-out Fault setpoint, the GSC+P will activate
AL18 Synchronizer Time-out Alarm and halt
synchronization. In this case, the alarm is latched
until the synchronization request is removed. If the
request was made locally using the SMS, then
the SMS must be moved to the OFF position to
CLEAR the alarm. If the request was made remotely
by a CCM, then the CCM must send a Generator
Synchonizer Control command (with a value of OFF)
to CLEAR the alarm.