Operation 55
3.1.6 Alarm Limit Settings Screen
Goto the Master Menu and move the highlighted cursor to LIMIT SETTINGS.P ress the Select pad and the
LimitSettings screen is displayed.
TheAlarm Limit Settings screen has Security Access to enable an authorized Liebertfield-service engineer to
adjust the UPS system alarm l imit settings.
Figure 35 Module Alarm Limit Settings Screen
OverloadAl arm (SCC and modules). This alarm settinginitiates an alarm messageon the display screenwarn-
ingthe operator that the UPS system output current has exceeded the specifiedlimit. This condition only acti-
vatesan alarm. The UPS does not shut down, but a separatecontrol circuit will transfer the criticalload to bypass
ifthe current and time of the overload condition exceeds systemcapability.
DCO ver-Voltage(modules only). This setting limitsthe maximum permitted level of theDC bus voltage.
Whenthis setting is exceeded, an alarm indication appearson the module display screen. The UPS module is
takenoff-line (the module output circuit breaker is tripped open), and theinput andbattery circuit breakers trip
open.
BatteryDisc harging (modules only). When the batteryvoltage on the DC bus falls below this limitfor 5 sec-
onds,a Battery Discharging alarm message is displayedon the module screen. This means that the battery is dis-
chargingdue to an input voltage sag or interruption, ora module output overload.
Low Battery(m odules only). Whilethe battery is discharging, this alarm warns the operatorthat the Battery
Shutdownlevel is approaching. This is typically set for a reserve time of approximatelyfive minutes (10 volts
abovethe 60-Minute Battery Shutdown Voltage),based on full load operation.
BatterySh utdown (15 Minutes) (modules only). When the batteryvoltage decreases to this limit for five sec-
ondsduring the first 15 minutes of the discharge, the battery circuitbreaker opens to prevent over-discharge.
Notethat the rated battery reserve timeat your site may be other than 15 minutes.
BatterySh utdown (60 Minutes) (modules only). During extendedoutages or deep sags of more than 15 min-
utes,the shutdown voltage limit will ramp up gradually to this 60-minutelimit to prevent lengthy discharge and
possiblebattery damage. The battery circuit breakerope nswhen the battery voltage and the shutdown limit are
equalfor five seconds. See the Battery Time screenfor more information. Also refer to the battery manufac-
turer’smanual.
BatteryRating (100%) (modules on ly). Thissetting is the full load discharge ratingof the battery in kilowatts
forthe rated backup period. A typical rating might be 500 kW for 15 minutes.
CAUTION
Allalarm limit settings are application matched and factory set.They should not
bechanged casually. Contact Liebert Global Servicesfor changing the alarm
limit settings.
EXIT
SECURITYACCESS CURSORUP
CURSORDOWN
CHOOSE
UP :
DOWN :
SELECT :
ALARM SETTINGS
CURSORUP
CURSORDOWN
CHOOSE
UP :
DOWN :
SELECT :
OverloadAlarm ...............................
DCOverVoltage ...............................
BatteryDischarging ...........................
LowBattery .......................................
BatteryShutdown (15m inutes) ......
UpperPoint (60minutes) ......
BatteryRating (100%) .....................
BatteryRating ...................................
104 %
600 VDC
480 VDC
437 VDC
384 VDC
427 VDC
500 KW 15 min
250 KW 45min
DISCONTINUED
PROD U C T