Power Supply, Low-voltage power supply | Brother 1240, HL-1030, 1250

CHAPTER 3 THEORY OF OPERATION

1.6	Power Supply
1.6.1 Low-voltage power supply
	The power supply uses a switching regulation system to generate the regulated DC power
	(+5V and +24V), which are converted from the AC line.
	The regulated output and the production code of each power supply are listed below;

	Regulated Output	Production Code
	+5V / 1.6 A	100V: MPW1555
	+24V / 2.15 A	200V: MPW1455

For the circuit diagram of the low-voltage power supply PCB, see Appendix 20 or 21.

Fuse

Lightning

Heater

Surge

Circuit

Absorber

Fuse

Line

Rectifier

Filter

(Heater)

Thermal

Fuse

Lamp

Feedback

Oscillator

24V

Regulation

Circuit

(Engin Circuit)

24V

5V

Regulation

Circuit

5V

Fig. 3-25

3-19

Image 61

Brother 1240, HL-1030, 1250 service manual Power Supply, Low-voltage power supply

Contents

SM-PRN001 Model HL-1030/1240/1250/1270NPage Preface Table of Contents Theory of Operation Disassembly and RE-ASSEMBLY Troubleshooting Periodic Maintenance Index Manufacturedc Manufacturedk For Finland and Sweden IEC 825 220-240V Model only Achtung Safety Information Definitions of WARNINGS, Cautions and Notes High Resolution and Fast Print Speed FeaturesQuick Print Setup Versatile Paper Handling Environment-Friendly Enhanced Memory Management Bar Code Print for HL-1250/1270N only Network Feature for HL-1270N onlyIsbn UPC-A UPC-E EAN-8 Front View OverviewRear View HL-1030/1240 HL-1250/1270N Printing SpecificationsDIB CPU Functions Electrical and Mechanical Paper Network for HL-1270N onlyFeedable paper General Print delivery Paper cassette capacity Printing Area Print guaranteed areaEffective printing area Monarch COM10 Power Supply Conditions Required for InstallationEnvironment Unpacking For Windows Users Install the Printer Installation and Basic Operation For Windows Users with No CD-ROM Drive Install the drum unitLoad paper Print a test Connect the printer and the computer Install the printer driver from floppy disk Install the USB driver Using the USB Interface for Windows 98 onlyConnect the USB interface cable Installation and Basic Operation Set the PC printer port For Macintosh iMac and Power Macintosh with USB Users Only Load Paper into the Paper Cassette Paper HandlingLoad Paper Manually To print on both sides of the paper from the paper cassette Two Side Printing Manual Duplexing Installation and Basic Operation Control Panel Operation AlarmDrum Ready Data Data Toner LED Indications Alarm LED IndicationsDrum LED Indications Sleep mode Other Control FeaturesControl Panel Button Operations Operation Description Test print mode Preparing the BR-net Board Network Board Operation for HL-1270N onlyConnect the Ethernet cable Factory default setting Print configurationLED functions LED green Link activity Electronics General Block Diagram RAM 4MB HL-1250 HL-1270N Shows a general block diagram of the HL-1270N printer Main PCB Block Diagram USB I/O CPU Core Reset Circuit Asic HL-1030/1240 Main PCB HL-1250/1270N Theory of Operation 2 ROM HL-1030/1240 Two 32 Mbits ROMs x 16 bit are fitted Dram HL-1030/1240 Flash ROM for HL-1270N only Two 16M-bit DRAMs x 16 bits are used as the RAM Optional RAM HL-1250/1270N PCI bus HL-1270N Optional serial I/O HL-1250 Eeprom HL-1030/1240 Reset circuit HL-1030/1240 Engine I/O HL-1030/1240 BR-net PCB for HL-1270N only Engine PCB Low-voltage power supply GND High-voltage power supply Overview of Printing Mechanism Mechanics PCB Paper supply Paper TransferPaper registration Paper eject SensorsCover sensors a and B Toner Cartridge Drum Unit Charging Print ProcessExposure stage Developing Fixing stage Transfer TAPTITE, CUP S Safety PrecautionsScrew PCBs Disassembly Flow AC Cord Disassembly Procedure Paper Cassette Taptite, Torx pan M3x8 Disassembly and RE-ASSEMBLY Side guide L Side guide R Paper cassette Paper cassette Release lever extension spring Lock lever ➀ ➁ Network Board for HL-1270N only Front Cover Top Cover Main Cover Tray extension flap Main cover Laser Unit Drive Unit Main motor Assy Grease Molykote PG-662 1 rice-grain size Fixing Unit Fixing unit Main frame Concavity Remove the fixing unit cover from the fixing unit frame Halogen lamp Taptite, pan M3x10 Heat roller bearing Washer Heat roller gear Heat roller gear Heat roller bearing Embossment Heat roller cleaner Fixing unit frame Cleaner spring Hooks Thermistor Fixing unit frame Taptite, cup M3x12 Fixing unit frame First eject roller Idle gear PR2000057 26B Base Plate Ground wire Plastic chute Slit Main frame Lower Tray Relay PCB Assy for HL-1250/1270N only Main PCB Assy Low-Voltage Power Supply PCB Assy 30A PCB Assy Engine PCB Assy / High-Voltage Power Supply PCB Assy Toner sensor light Solenoid Assy Panel PCB Assy Clutch lever spring For paper feed roller Step Cassette guide L/F Taptite, cup M3x6 Fan Motor Assy Toner Sensor PCB Assy Light Reception Toner Sensor PCB Assy Light Emission Paper Pick-up Roller Assy Paper Feed Roller Assy 70a Outer Chute Packing Consumable Parts Replacement Procedure Toner Cartridge Periodic Maintenance Assy Periodical Replacement Parts Cleaning the Printer Exterior Periodical CleaningCleaning the Drum Unit Clean the Electrical Terminals Cleaning the Scanner Window Mtbf / Mttr Periodic Maintenance Initial Check Introduction Troubleshooting Printer does not print Printed page has a problem Identify the Problem Service Calls Operator Calls & Service CallsLED Indication Error Remedy Operator Calls How the LEDs indicate an error See ‘M-11 Service B’ Error Messages in the Status Monitor Error MessagesError Message Remedy NV-RAM Error RAM ErrorMain Motor Error Error Error Message Printouts Paper Loading Problems Paper ProblemsProblem Remedy Clearing jammed paper Paper Jams Causes & countermeasures Problem Type of Jam Cause Remedy Double feeding Paper Feeding ProblemsWrinkles or creases User Check Curl or Wave Skew Subsection 10.1 ‘Test Print Software Setting Problems Unable to print from application software under DOS HL-1240/1250/1270N only Value or alphabet following ‘BR’ is a product ID No DC power supplied No AC power suppliedMalfunctions PCB No paper supplied Main motor does not rotate Fixing heater temperature failure Insufficient output from high-voltage power supply unitBD failure Fuser failure Scanner failurePCB 24V DC? Engine interface error ROM error / D-RAM error / NV-RAM errorPCI BUS error HL-1270N only Image Defect Examples Image Defects Light Troubleshooting Image Defect Dark Completely blank All black Dirt on the back of paper How to clean the pressure roller Black and blurred vertical streaks Black vertical streaks in a gray background Black and blurred horizontal stripes White horizontal stripes White vertical streaks Poor fixing Faulty registration Faint print Image distortion White spots Photosensitive drum Black band Black spots Hollow print Gray background Horizontal lines Downward fogging of solid black Ghost Light rain Toner specks Drum unit Location of Grounding ContactsPrinter body & Paper cassette Printer prints unexpectedly or it prints garbage Incorrect Printout For HL-1250/1270N only User Check For DOS environment only User Check For connecting by RS-232C/422A on HL-1250 only Installation Problem Network Problem for HL-1270N only Intermittent Problem Unix Troubleshooting TCP/IP Troubleshooting Windows 95/98 Peer to Peer Print LPR Troubleshooting Windows NT/LAN Server TCP/IP Troubleshooting Internet Print TCP/IP Troubleshooting AppleTalk Troubleshooting Novell Netware Troubleshooting Apple TCP/IP Printing System 8.6 or later Web Browser Troubleshooting TCP/IP Test Print Mode Inspection ModeType of mode Function For the demo printer Type of inspection Inspection Mode Alarm Factory inspection modeDrum Ready Troubleshooting Troubleshooting Biuk Appendix 1. Serial NO. Descriptions 0 0 1 0 Appendix 2. Diameter / Circumference of Rollers Media type setting All models Appendix 3. Print Speeds with Various SettingsMedia type setting HL-1240 demo model Print Configuration for HL-1240/1250/1270N only Appendix 4. HOW to Know Drum Unit Life & page Counter Fig. A-2 Test Print for HL-1030 only How to calculate drum unit life How to Read the Drum Unit Life How to Read the Page Counter Fig. A-4 How to Read the Maintenance Information Fig. A-7 Troubleshooting for Printer won’t print Appendix 5. HOW to USE the SELF-DIAGNOSTICS Tools Fig. A-10 Diagnostics If you click the OK button in , the dialog box below appears Fig. A-13 Printer Information Items Descriptions Appendix 6. Nvram Default Value Fig. a Appendix 7. Paper Cassette Information for Europe only Appendix 8. Connection Diagram, HL-1030/1240 Appendix 9. Connection Diagram, HL-1250 Appendix 10. Connection Diagram, HL-1270N Appendix 11. Main PCB Circuit Diagram, HL-1030/1240 1/2 Appendix 12. Main PCB Circuit Diagram, HL-1030/1240 2/2 Appendix 13. Main PCB Circuit Diagram, HL-1250/1270N 1/5 Appendix 14. Main PCB Circuit Diagram, HL-1250/1270N 2/5 Appendix 15. Main PCB Circuit Diagram, HL-1250/1270N 3/5 Appendix 16. Main PCB Circuit Diagram, HL-1250/1270N 4/5 Appendix 17. Main PCB Circuit Diagram, HL-1250/1270N 5/5 Appendix 18A. Engine PCB Circuit Diagram OLD Appendix 18B. Engine PCB Circuit Diagram NEW Appendix 19. Network Board Circuit Diagram, HL-1270N Low-voltage PS Circuit 110 Low-voltage PS Circuit 220 High-voltage PS Circuit CN1 CN2 DEV1 Electrode helical spring / Chute High-voltage power supply PCB / Engine PCB Index Electrical terminal 22,4-30 2-10, 4-4, A-16 1-4 Index PL-PRN001 Parts Reference List B48K056 201A REF.NO Code ’TY Description Symbol Remark Contents Main Motor Assy REF.NO Code QTY Description Symbol RemarkTAPTITE, CUP S M3X6 Solenoid Assy Frame / Drive Unit Bearing JointConductor Bearing Paper Feeder Cleaner Spring Cleaner Roller AssyREF.NO Code QTY Description Remark Fixing UNIT, 115V SP Fixing Unit Paper Tray ASSY, LGL SP Paper IndicatorPressure Plate ASSY, LGL Pressure Plate Spring Pressure Roller Holder Paper Tray Assy 3 SPPaper Tray ASSY, LEG SP Paper Cassette TOP Cover Rear Cover10 UL9142001 1 Second Eject Roller Assy Model Plate Covers Main PCB ASSY, HL-1240 SP Main PCB ASSY, HL-1030 SPMain PCB ASSY, HL-1240 HEB SP Main PCB ASSY, HL-1240 PB SP HL-1030 HL-1240 HL-1250 HL-1270/1270N Engine PCB Assy A, 1250 SP Engine PCB Assy A, 1240 SPLOW-VOLTAGE PS ASSY, 115V SP LJ8330001 1 Protection Tube Engine PCB AC Cord ASSY, SAA AC CORD, UL/CSAAC Cord ASSY, SEV AC CORD, Chli High Voltage Power Supply PCB Setup GUIDE, GER Setup GUIDE, FRASetup GUIDE, NL Setup GUIDE, NOR Accessories CARTON, HL-1030 EU Accessory CartonCARTON, HL-1030 can CARTON, HL-1240 US Packing Materials Torx Screw Driver Tool no Tool Name RemarkMolykote PG-662 ADD