Emerson 250-400kVA - Manual (Page 53)

UPS Alarm and Status Messages
47
Breaker Close Fail
This is a summary event that informs the user that
a circuit breaker that was either signaled to close
or was manually closed failed to report a closed
status.
The Breaker Close Fail event indicates a
mismatch between the expected state of a
breaker and the reported state of the breaker.
Press “SILENCE” to silence the audible alarm.
Check the One-Line Display and the Active Event
Window to determine which breaker or switch is
open.
If the open breaker cannot be reset or closed, or if
all breakers are closed but the One-Line Display
does not agree, or the alarm cannot be cleared,
contact your factory-authorized service provider.
Breaker Open Fail
This is a summary event that informs the user a
circuit breaker that was either signaled to open or
was manually opened failed to report an open
status.
The Breaker Open Fail event indicates a
mismatch between the expected state of a
breaker and the reported state of the breaker.
Press “SILENCE” to silence the audible alarm.
Check the One-Line Display and the Active Event
Window to determine which breaker or switch that
should be open is still closed.
If a breaker that should be open shows closed, or if
the breaker in question actually is open but the fault
is still present, attempt to clear the fault by pressing
“RESET.”
If the event does not reset, contact your factory-
authorized service provider.
Byp Overload
Ph A
The critical load is greater than 110% while the
UPS is on bypass. The controls may shut the unit
down if the overload condition does not clear
within the allotted time. Allotted time is variable,
and is inversely proportional to the amplitude of
the overload, i.e., the greater the amplitude of the
overload, the less time the unit continues to
support the load.
This alarm is self-clearing. When the condition is
no longer present, the alarm and any control
activity tied to the alarm reverts to normal.
Press “SILENCE” to silence the audible alarm.
Observe the calculated load percentage on A phase
displayed on the Module Output Meter. If the A
phase steady state load percentage exceeds 110%,
perform the following:
If Maintenance Bypass is available, follow Standard
Operating Procedures to transfer the load to
Maintenance Bypass.
If Maintenance Bypass is not available but the
system has an Internal Bypass Breaker (CB3 on the
One-Line Display), close CB3. Note that depending
on the severity of the overload, the possibility exists
that CB3 could trip if the overload exceeds the
breaker rating.
Investigate the overload condition.
If the Module Output Meter does not indicate an
overload condition, perform the previous steps and
contact your factory-authorized service provider.
Byp Overload
Ph B
The critical load is greater than 110% while the
UPS is on bypass. The controls may shut the unit
down if the overload condition does not clear
within the allotted time. Allotted time is variable,
and is inversely proportional to the amplitude of
the overload, i.e., the greater the amplitude of the
overload, the less time the unit continues to
support the load.
This alarm is self-clearing. When the condition is
no longer present, the alarm and any control
activity tied to the alarm reverts to normal
Press “SILENCE” to silence the audible alarm.
Observe the calculated load percentage on B phase
displayed on the Module Output Meter. If the B
phase steady state load percentage exceeds 110%,
perform the following:
If Maintenance Bypass is available, follow Standard
Operating Procedures to transfer the load to
Maintenance Bypass.
If Maintenance Bypass is not available but the
system has an Internal Bypass Breaker (CB3 on the
One-Line Display), close CB3. Note that depending
on the severity of the overload, the possibility exists
that CB3 could trip if the overload exceeds the
breaker rating.
Investigate the overload condition.
If the Module Output Meter does not indicate an
overload condition, perform the previous steps and
contact your factory-authorized service provider.
Table 7 Liebert NXL alarm and status messages (continued)
Event Message Event Definition Recommended Action