Operation 63
Figure 42 Battery Time Screen Example - 45 Minute Discharge
TheBattery Time Remaining graph and the Calculated times are extremelyhelpful to the operator who has the
discretionaryauthority to order load-shedding activities.The Series 600T automatically samples battery voltage
andload current and recomputes every six seconds. Thisgives the operator fast and accurate feedbackon efforts
toextend battery time remaining by shutting down non-criticalloads.
TheSeries 600T dynamically adjusts the Battery Shutdown voltagebased on battery characteristics and the
lengthof the current discharge event. If a dischargeevent extends past 15 minutes (i.e., the load is less thanthe
fulldesign rating), the Battery Shutdown voltage setting is graduallyand automatically increased, to protect the
batteriesfrom deep discharge.
When the battery voltage decr eases to a preset limit (see 3.1.6 - Alarm Limit Settings Screen), the Low Battery
Warningalarm message appearson the display screen. This warns the operatorthat the battery voltage is
approachingthe Battery Shutdown level—about five minutes of time remaining atfull rated load.
Ifthe battery discharges to the Battery Shutdownlevel, represented by the lower line on the Battery Timescreen,
thebattery and input circuit breakers trip open and the UPS module is shut down. This protectsthe battery from
beingdamaged by an extended deep discharge.
NOTE
Whileevery effort has been made to make the Rated and CalculatedTime Remaining
valuesas accurate as practical, these values mustbe regarded as approximations.At
thebeginning of the discharge cycle, theCalculated times could be off by as much as
±20%due to such variables as battery initial charge, ageof battery, and the
subsequentload-shedding activities of the operator.Within a few minutes, however,
thesecalculations should settle into theirdesign accuracy of ±10%, with the end-of-
dischargetolerance being +0, -10% of actual observedtime. In addition, the
operatorcan adjust the settings affecting Rated TotalTime after gaining experience
withthe actual battery and connected load.
NOTE
TheLow Battery alarm setting is designed to be useful at fullload battery discharge
rates.Unlike the Battery Shutdown voltage, the LowB atteryalarm setting is not
automaticallyincreased and shouldnot be relied upon as an indicatorof battery time
remaining.Instead, the operator should consultthe Battery Time screen or Present
Statusscreen to see the Calculated TimeRemaining based on actual usage during the
dischargeperiod.
0 10 20 30 40 50 60
Time (Minutes)
340
360
380
400
420
440
460
480
500 VDC
BatteryShutdown = 417
BatteryCharge = 3%
Total00:45 Remain0:01
RatedTime (Hrs:Min)
Total00:25 Remain0:00
SELECT: MASTER MENU
LowBattery Warning
CalculatedTime (Hrs:Min)
DISCONTINUED
PROD U C T