Samlexpower BBM-1225 - Description and Principle of Operation; Description; Principle of Operation

4 | SAMLEX AMERICA INC. SAMLEX AMERICA INC. | 5
SECTION 3 | Description and Principle of Operation
3.1 DESCRIPTION
Thisunitisusedtoallowany12VDC/24VDCpowersupply(withratedCurrentLimit
valueofupto25A)tofunctionasaDCUninterruptedPowerSource(UPS).Thisunitis
apassivedeviceandfunctionsonlyasaninterfacebetweentheexternalpowersupply,
thebatteryandtheDCload.Aslongasthepowersupplyisoperatingnormally,itwill
supplytheloadaswellasoatchargethebattery.
Incasetheoutputofthepowersupplyfails,thebatterywillstartfeedingtheload
immediatelythus,ensuringuninterruptedDCpowertotheload.Duringthisperiod,
thebatterywillstartdischarging.Oncetheoutputofthepowersupplyisresumed,
thepowersupplywilltakeovertheloadandwillalsore-chargethebatteryatitsoat
voltage.
3.2 PRINCIPLE OF OPERATION
i
INFO
Explanationgivenbelowisbasedonuseofexternalpowersupplywith
"ConstantCurrentLimit"valueof25A.InaConstantCurrentLimitPower
Supply,whentheCurrentLimitvalueisreached,theoutputvoltagewillnot
beregulatedandwilldrop.
R1
R2
D2D1
INPUT
INPUT
BATTERY
LOAD
D1,D2
R1,R2
SCHOTTKY DIODE, 30V/30A
POWER RESISTOR 1R2 (1.2 OHM), 25 WATTS
+
+
+
+
EXTERNAL
POWER SUPPLY
+
BATTERY
FUSE F1
32V, 25A (FAST BLOW)
FUSE F2
32V, 25A (FAST BLOW)
+
LOAD
Fig. 3.1: Schematic and Installation Diagram
PleaserefertotheschematicandinstallationdiagramatFig.3.1.