Setec ST-III Series - Functional Diagram; ST-III Basics

FunctionalDiagram
STIIIBasics
AC/DCPowerSupply:Thisprovidesanisolated13.65Vdcoutputforpoweringof
theloadandfloatchargingofthebattery.Batterycurrentissensedandmonitored
bythepowersupplytoensurethatthemaximumchargingcurrentisnot
exceeded.
BatteryFeatures:Thepowersupplyprovidesfullbatterymanagementasperthe
following.
ThepowersupplyisafourstagebatterychargerwithBoost(VBoost=14.05V),
Float(VFloat=13.65V),Store(VStore=13.25V)andTricklechargemodesto
ensurelongbatterylife.
BatteryChargingcurrentislimitedtoamaximumof10A(ST20III)and15A
(ST35III).Thisprovidesoptimumlifeforthebatteries.
Tochargeatthemaximumbatterychargecurrentabove,ensuretheloadcurrent
plusbatterycurrentisequalorlessthanthemaximumoutputcurrent.The
chargingcurrentwillbereducedinsituationswherethedifferencebetweenthe
ratedoutputcurrentandtheloadcurrent(theavailablechargingcurrent),isless
thanthemaximumchargingcurrent.
Alsonotethatthebatterycurrentsenseisprovidedinthe“Batt+ve”battery
output.Forthisfeaturetowork,theload“+ve”andbattery“Batt+ve”shouldnot
becrossconnected.(Appliancesshouldnotbeconnectedtoboththe“Batt+ve”
and“+ve”terminalsofthepowersupply.Appliancesshouldbeconnectedtothe
“+ve”and“ve”loadterminals).
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Figure1:FunctionalBlockDiagram
ACInput
8xLoad
Outputs
CaravanBattery
AC/DC
Vadj
BatteryLowvoltage
DisconnectCircuit
LoadRemote
disconnectCircuit
RemoteLoad
on/offInput
Battery–Ve
8xLoad
Returns
CarBattery
BAT–VE
BAT+VE
DCIN+VE
–VE
L1–L8
LOADSWITCH
BATERYFUSE
LOADFUSES
0.8A
Trickle