EnerSys Alpha Cordex CXC HP - Battery Runtime and Health Estimation; Figure 5-2 Temperature Compensation Voltage Graph

Cordex®CXCHPControllerSoftwareManual|5-DCpowersystems
Figure 5-2 Temperaturecompensationvoltagegraph
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TemperatureCompensation
BatteryVoltageCurve
Voltage(V)
Temperature(°C)
UpperTemperatureBreakpoint
LowerTemperatureBreakpoint
Batteryperformanceandlifeexpectancyaredirectlyrelatedtothebatteryambienttemperature.The
optimumoperatingtemperatureforbatteryoperationistypically25℃ (77℉). Abovethistemperature
batterylifemaybereducedandbelowthistemperaturebatteryperformancemaybereduced.
Thermalrunawayoccursiftheinternaltemperaturerisesduetoovercharge,highambienttemperatureor
internalfault.TempCompautomaticallyadjuststhefloatvoltageasthebatterytemperaturechangesto
protectthebatteryfromthermalrunaway.
TheTempCompfunctionadjuststhesystemvoltageeverytwoseconds,asthetemperaturechanges,
andprovidesforamaximumvoltagechangeof0.2Voverthisinterval.TempCompoccursatstandard
ratescommonlyreferredtoasslope-compensationsettings.
TheslopeoftheTempCompcurveineithermV/°F/CellormV/°C/CellcanbesetviatheSystems > DC
System > System Functions > Temperature Compensation menuintheConfiguration table.The
valueissetbasedonthebatterymanufacturer’sinformation.
Sinceabatterycanhavemultipletemperaturesensors,temperaturecompensationusestheaverageof
thetemperaturereadingstodeterminethebatterytemperatureonwhichtoadjustthebatteryvoltage.
Theaverageisusedaslongasallthetemperaturereadingsarewithin5℃ (9℉) ofeachother.When
atemperaturereadingrises,perhapsduetolocalheatingorthermalrunaway,andreachesapoint
whenthehighesttemperaturereadingis5℃ (9℉) greaterthanthelowesttemperaturereading,then
temperaturecompensationwillusethehighesttemperaturereadingtodeterminethecompensated
batteryvoltage.Thiswillresultinalowerbatteryvoltageandreducetheriskofthermalrunaway.
Ifoneormorebatterytemperatureprobesappeartobedisconnectedorbroken,thentheTempComp
functioncalculatestheenabledsetpointsasifthetemperaturereachedtheUpper Temperature
Breakpoint. Thisisthesafestoptionincasethefailedsensorhappenedtobetheonewiththehighest
temperaturereading.
5.2.5. Battery runtime and health estimation
Battery Estimation canbeenabledviatheSystems > DC System > System Functions > Battery
Runtime & Health menuintheConfiguration table.Whenenabled,thecontrollercalculatesan
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