Sharp SD-AT1000W Spécifications télécharger pdf (Page 177)

Maxiva UAX

October 17, 2013

4‐13

888‐2693‐004 WARNING:Disconnectprimarypower priortoservicing.

4.3.12 BatteryBackup,UPS(FutureOption)

ThisUPSversionofbatterybackupboard(971‐0051‐012G)willrequireuseofthelowvoltagePSboard971‐0051‐

011G.

Note

Current versions of the low voltage PS board (971-0035-007) use battery backup board assembly (971-

0035-003G ).

TheUPSbatterybackupboardinterfacesdirectlytotheLVPSboard.ThreeLithium‐ioncellsareusedinaseries

arrangementandprovide9.6voltsat1200mAh,12WHrrated.Thebatterybackupassemblyconsistsofabattery

backupcircuitboardwiththreeLithium‐ioncellspermanentlyattached;italsoincludesacu

stombatterycharging

circuitandprotectioncircuitry.Thebatteriesandcircuitboardaresoldasaunitwhenreplacementbatteriesare

required.

Thebat

terybackupassemblypartnumberis971‐0051‐012G.

Theb

atterybackupsuppliestheLVPSboardwith+6.4Vto10.8Vat20Amaximum.ItismounteddirectlytotheLVPS

board.AblockdiagramofthebatterybackupassemblyisshowninFigure4‐9.

Thebat

terybackupassemblyspecificationsareasfollows.

• Rechargetimeforthefullydischargedbatterypackistwotothreehours.Thechargecyclestartsandstops

basedonthebatterypackoutputvoltage.

• Undertheoptimumbatterycondition,thisbatterybackupoptioniscapableofoneminuteofoperationof

themodulatorportionoftheUAXtransmitterfollowinganacpowerfailure.Thisisaccomplishedbykeeping

the+24V,+12V,+12Vosc,+5V,and‐12Vpowersupplyinterfaceboarddcoutputsenergizedforoneminute

ollowingapowerfailure.Duringthistimethe PAassemblyisnotpowered.

• ItkeepstheoscillatorcircuitsandtheinternalGPSreceiveroperatingforanadditionalfifteenminutesfollow‐

ingth

eoneminutemodulatorbackupoperation.Itaccomplishesthisbyde‐energizingallbutthe+12Vosc

powersupplyoutputs.

• Duringthelastfifteenminutesofbatter ybackupoperation,thebatterybackupmaintainspowertothe

10MHzand1PPSInputcircuitryontheSignalProcessingboardandtheFPGA,OCXOandGPScircuitryonthe

PFRU.Bypoweringthesecircuitsthemodulatorcanmaintainthe10MHzOCXOdisciplineloopwhenthe

ransmitterlosespower.TheOCXOcantakethreeminutestostabilizefromacoldstartandthediscipline

loopitselfcantak eanhourtoreachthemaximumprecision;havingthedisciplineloopactiveduringapower

outageenablestheUAXtransmittertoreturntoairfasterwithgreaterfrequencyaccuracy.



Figure 4-9 Battery Backup Block Diagram

1 2 ... 172 173 174 175 176 177 178 179 180 181 182 ... 291 292

Sharp SD-AT1000W Spécifications Page 177