Xylem MJK Chatter, Hardware Installation User Manual

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Appendix B. Calculation of Battery Lifetime
ThebatteryintheMJKChatterunitisofthelithium-trionyl-ion-trotyltype
whichischaracterizedbyahighenergydensity,alowself-discharge,and
alonglifetime .Theenergydensityis17Ahnominalandguarantied15Ah
(15 .000mAh) .DependingontheuseoftheChatterunityoucanestimatethe
batterylifetime .
TheChatter

will,dependingonthesetup,executeonecontrolcallevery25th .
hour(ifashorterintervalhasnotbeenselected) .Thisensuresthatyoucan
alwaysmakechangestothesetupefter25hours .MJKrecommendsthat
youperformacallevery24hours(onceaday)ormorefrequent .
Thelifetimecalculationissimpleforusageswithafixedloginterval,whereas
usageswitheventlogrequireatimeestimationfortheeventlogs .
Calculation Template
Chatterbasicconsumptionperday(fixed)=    1 .0
No .oflogsperday@sensorconsump .=2mA ? x 0 .1= -
No .oflogsperday@sensorconsump .=4mA ? x 0 .2= -
No .ofeventlogsperday@sensorconsump .=2mA? x 0 .1= -
No .ofeventlogsperday@sensorconsump .=4mA? x 0 .2= -
No .ofcallsperday    ? x 3= -
No .ofalarmcallsperday   ? x 3= -
Consumptionperday(total):      -
Batterylifetimeindays: 15000/consump .perday[day]=  -
Batterylifetimeinmonths: Batterylifetime[days]/30[months]= -
Battery lifetime in years
: Batterylifetime[months]/12[years]= -
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AppendixB .CalculationofBatteryLifetime
Data Logger
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