Samsung RM255BASB, RM255BABB manual Power BUS, A voltage proportional to

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Circuit Descriptions

12-1) POWER BUS

This POWER BUS, and SMPS (Switch Mode Power Supply), is an improved efficiency power- convertion circuit for converting AC input voltage to high voltage DC. However, a consistent attention should be paid to the POWER BUS because 115V AC and 170V DC may be generated. The voltage input has AC applied into BD1(Rectifier Circuit) through FUSE(F1) and LF1, and smoothes the rectified voltage through C101(180uF/450V). As a result, DC voltage is applied into the SMPS TRANS. At the same time, the rectified DC voltage is applied into No 2. of U5(TOP246Y)08 through R24 and R25, and starts initial IC operation. With the role of SNUBBER Circuit (D1, R18, C7, TVS1, C8), also controls the switching wave-formed P-P voltage to protect U5 IC. R21(2W470K) is the parts that special regard must be paid to the safety against potential electric shock during SVC, which is charged with power ON and discharging electricity with power OFF. When the initial operating voltage is applied into U5 No.2 PIN, the U5 IC starts high speed (130KHz) switching operation. And then the input voltage is applied into NP1 (primary winding) of TRANS first,

and a voltage proportional to

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Contents RM255BARB RM255BASB RM255BABB Authorized Training Center Campuses Important Safety Notice Contents Precautionssafety Warnings Symbols Forbidden Product Specifications This operation instruction covers various models ManualModel Specification RM25After packing 386lbs Electric Parts Specification SensorItems Specifications Model Dispenser Home BarElectric Components RunningOptional Material Specifications PhotographPart Code Operating Instructions & Installation Temperature Control Operation Digital PanelPower cool Operation Power Freeze and Power cool OperationPower Freeze Operation By in inside function irrespective of current settingAble to operate on front panel At Initial Power OnLock Function Cube / Crushed / ICE OFF Selection FunctionLight Operation Machine Room F-Fan Motor Delay FunctionWater Dispenser Function Load Operation ConditionHorizontal position Interval about 880ms Initial OperationReverse rotation CCW Forward rotation CW Ice extraction Maximum torsion pointIce Extraction Function Water Supply FunctionIce-Making Function Water Supply TimeBold numerals indicate relevant ice tray steps Horizontality operation Arctic Zone Defrosting FunctionDefrosting period is fixed to 8 hours 53.6 62.6Operation Arctic Select Zone FunctionFunction Fresh Select Zone FunctionTest KEY Function Operation SpecificationTemp .8 ~ 44.6 of the Fridge compartment Operation startForced Defrosting Function For the R compartmentWhen water supply is finished, in the ice maker test mode Alarm FunctionCommunication Error Display Function Display Function at PanelOperating Instructions & Installation Self-Diagnostics FunctionSelf-Diagnostics Checklist BAD Item Trouble StatusSensor of R ErrorDefrosting CR SensorOn Error CF-FAN ErrorCR-FAN Error TroubleLoad Mode Checklist Load Item Load Status Load Condition Display FunctionRelevant displays about load status is as follows Changing to Optional Mode Option Setting FunctionKEY Function Value ItemTemperature Change Table for the Freezer Compartment Change for freezer compartmentTemperature Change Table for the Refrigerator Compartment KEYMaker For Ice Maker CR Room Temperature Shift FunctionCase of basic model, the following items cannot be set Flow sensorDisassembly and Reassembly Removing the Front Leg Cover Door AssyRemoving the Freezer Door Removing the Refrigerator Door Open the Fresh Select Zone Door Remove two screws holding it toLiner on the right side of the rail To separate it Reattaching the Freezer Door Reattaching the Refrigerator Door Levelling Open the Arctic Select Zone Door ZoneDo not overtighten the compression Note nut Water line must be connected to drinkable water onlyClose the filter cartridge cover Door Handle Door Sub PartsControl Panel Door GasketTempered Glass Shelf Refrigerator Door Light SwitchRefrigerator Light Plastic Drawers in the RefrigeratorDoor Bin in Freezer Freezer Door Light SwitchFreezer Compartments Plastic Drawer in FreezerIce Dispenser Ice Maker Tighten the screws 2 of the ice maker supportFreezer Light Auger Motor Case Upper DuctworkPartition in the Freezer Screws Pull the upper part of the evaporator cover slightlyEvaporator Fan Motor Evaporator in FreezerIce-Maker Thermistor Freezer ThermistorThermistor cover Screw Water TankEvaporator cover in the Refrigerator Evaporator Fan Motor in RefrigeratorDuctwork Thermistor Thermistor cover Evaporator in FridgeRefrigerator Thermistor Fresh /Arctic Select ZoneTM ThermistorUpper Ductwork Sub-condenser Machine Compartment Electric BoxPCB-MAIN Assy Water SolenoidsRemoving the Arctic Select Zone Accessories Normal If power is not onStart Check at the Smps PBA Check Main PCB connectionCheck connector for Contact failure Exchange and repair COMP. AssemblyIf the compressor doesn’t work normally Reference Perform forced defrosting for F R room one at a timeIf there is a trouble with self-diagnosissensor failure If the ambient temperature sensor has troubleHow To Check Temperature Sensing in the manual Check the soldering on the main PCB for Shorts & breaksIf Beep sounds continuously Start Alarm Sounds continuouslyrelated to the buzzerIf Ding-Dong sounds continuously Start Gasket, food etcBuzzer is broken - replace it If the buzzer doesn’t soundMain PCB is normal, buzzer is Normal Replace buzzer or panel PCBWhere the Panel PCB key isn’t selected If the panel PCB is not working normallyIt is a care Door Open 0V DC If fan motor doesn’t working normalyDoor S/W ConditionThese signals will be inputted into Micom Door Open DCIf Ice Cubed or/and Ice Crushed dont work normally If Indoor Lamp of Freezer/Refrigerator doesn’t light Replace Inside lamp Replace or troubleshoot Door S/WIf Water Drawer doesnt work normally Preliminary Check If Dispenser LED Lamp doesnt light Replace connector Wire and switchReplace connector and wire Failure of panel PCB itselfWiring Diagram Connector Arrangement Main Board Circuitschematic Diagram Conn Ector Arrangement SMP S Board Power BUS A voltage proportional to68.2 98.993.7 40.0 88.9 38.2 84.2 36.4 79.8 34.6 75.7 32.8 71.8 64.7IC75 Input IC75 Output FAN #18 GND0.8V107 Comparison in HIGH/LOW Speed Motor Drive Circuit DescriptionsPrinciple of Operation RemarksXAA 13-2 Q & a Problem Possible Causes What To Do Reference InformationProblem Possible Causes What To Do Small or hollow cubesAdditional Information Compressor Sub-condenser Hot Pipe Dryer Step valveSuction Pipe Freezer Refrigerator