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4

4

4-1

Samsung Electronics

Summary of product

Service Manual

4. Summary of Product

This chapter describes the functions and operating principals of the main components.

4.1 Printer Components

4.1.1 Front View

Output Support

Top output tray 
(Face down)

Control Panel

Power switch

Paper level indicator

Tray

Multi Purpose Feeder

Front Cover

Summary of Contents for ML-2251N

Page 1: ...mary of Product This chapter describes the functions and operating principals of the main components 4 1 Printer Components 4 1 1 Front View Output Support Top output tray Face down Control Panel Power switch Paper level indicator Tray Multi Purpose Feeder Front Cover ...

Page 2: ...4 2 Summary of Product Samsung Electronics Service Manual 4 1 2 Rear View Rear output tray Face up Power receptacle Parallel port USB port ...

Page 3: ...ing In Manual Feed mode if there is no paper in the Manual Feeder the On Line Error LED blinks red Load paper into the Manual Feeder and the LED stops blinking If the printer is receiving data the On Line Error LED slowly blinks green If the printer is printing the received data the On Line Error LED blinks green quickly If you press the Cancel button in Ready mode this LED is on and the Toner Sav...

Page 4: ...press and hold this button for about 10 seconds until all LEDs turn on and release After cleaning the printer one cleaning sheet is printed Canceling print job Press this button during printing The On Line Error LED blinks while the print job is cleared from both the printer and the computer and then return to Ready mode This may take some time depending on the size of the print job In Manual Feed...

Page 5: ...Bi polar 2 phase motor It drives the OPC Paper Pick up and paper feed rollers using a gear train mechanism d Image development unit Using a Laser Scanning Unit LSU this section of the mechanism creates the image on the OPC drum part of the integrated toner cartridge e Image transfer unit The function of the this unit uses High Voltages supplied by the HVPS to move the image from the developer unit...

Page 6: ...tronics Service Manual 4 2 2 System Layout PIC K R L S U Toner Cartridge PR Fuser EXIT Sensor OPC CR DR SR TR FR 1 1 2 2 3 6 3 4 Cassette Manual Feeder Transfer Roller 5 6 5 Fuser LSU Laser Scan Unit Toner Cartridge 4 MP Sensor MP Sensor ...

Page 7: ...he amount of paper remaining 3 Pick up roller The pickup roller is used to pick up and feed paper into the printer It also is used to remove any static charge on the paper 4 MP tray The Multi purpose tray is used to hold non standard paper sizes and special media envelopes transparencies etc There is an MP paper empty sensor It uses a friction pad method to ensure paper separation and can hold a m...

Page 8: ...eres to the surface of the paper permanently 4 2 6 4 Safety features To prevent overheating 1st protection device Hardware cuts off when overheated 2nd protection device Software cuts off when overheated 3rd protection device Thermostat cuts off mains power to the lamp Safety device Fuser power is cut off when the front cover is opened LSU power is cut off when the front cover is opened The temper...

Page 9: ...eveloping Method Non magnetic 1 element contacting method Toner Non magnetic 1 element shatter type toner The life span of toner 5 000 sheets ISO19752 standard Toner remaining amount detecting sensor No OPC Cleaning Film OPC using an electro static cleaning process Management of waste toner Collected using an electro static process and retained within the toner cartridge no waste toner to dispose ...

Page 10: ... main board from the power supply PBA 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 8 LOW DROP FIXED AND ADJUSTABLE POSITIVE VOLTAGE REGULATORS LD1117DT U1 LOW POWER DUAL BIPOLAR COMPARATORS LM393D U2 SPREAD SPECTRUM CLOCK GENERATOR CY25811 U4 CPU X TAL 12MHz OSC1 SDRAM K4S641632H U6 U15 LOW VOLTAGE HEX INVERTER WITH 5V TOLERANT SCHMITT TRIGGER INPUTS 74LCX14 U7 MOTOR DRIVER A3977SLP U9 GRAPHIC PROCES...

Page 11: ...ller Motor Control Unit Motor Speed Lookup Table Memory 128 x 16 x 2 Pulse Width Modulation Unit 4 Channels are supported ADC Interface Unit 3 ADC Channels are available ADC Core ADC8MUX8 maximum clock frequency 3 MHz USB 2 0 Interface Package 272 pins PBGA Power 1 8V Core 3 3V IO power operation Speed 166MHz core ARM946ES operation 60MHz bus operation 4 3 2 Memory The ML2250 has Flash ROM and DRA...

Page 12: ...ec after paper is fed a paper jam0 occurs Red ERROR LED is lit 4 3 5 4 Toner Remain Sensing The ML2250 does not have a toner sensor fitted 4 3 5 5 Paper Exit Sensing This detects that paper exits cleanly from the set using an exit sensor on the engine board and actuator on the frame The CPU detects the on off time of the exit sensor and normal operation or jam status is reported If a Jam 2 error o...

Page 13: ...e while controlling the fusing process the error stated in the table occurs For the domestic model the Q PID method has been applied Error Type 4 3 5 10 LSU The LSU consists of the LD Laser Diode and the polygon motor control When the printing signal occurs the LD is turned on and the polygon motor is enabled When the light sensor detects the beam Hsync occurs When the polygon motor speed becomes ...

Page 14: ...V and 24VS supplies to the main and other PBAs The HVPS creates the high voltage of THV MHV Supply Dev and supplies it to the toner cartridge The CPU is used to modify some of these voltage settings to provide the ideal voltages to create the image The HVPS part uses the 24V and outputs the high voltage for THV MHV BIAS and the outputted high voltage is supplied to the toner OPC cartridge and tran...

Page 15: ... Duty cycle of the THV PWM Signal 10 Duty 650V 90 Duty 5KV 5 2 Charge Voltage MHV Input Voltage 24 V DC 15 Output Voltage 1 3KV 1 8KV DC 50V Output Voltage Rise Time 50 ms Max Output Voltage Fall Time 50 ms Max Output Loading range 30 MΩ 1000 MΩ Output Control Signal MHV PWM CPU is HV output when PWM is Low 3 Cleaning Voltage THV The Transfer Voltage is not output because the THV PWM is controlled...

Page 16: ...AC 90V 135V AC 198V 264V EXP version Rated Frequency 50 60 Hz Frequency range 47 63 Hz Input Current Under 4 0A rms 2 0A rms When the fuser lamp is off and input output voltages are in range 2 Rated Output Power 3 Consumption Power NO Item CH1 CH2 CH3 System 3 3V 5V 24V 1 Stand By 1 0A 0 07A 0 4A AVG 55 Wh 2 PRINTING 1 0A 0 14A 2 0A AVG 280 Wh NO Item CH1 CH2 CH3 Remark 1 Channel name 3 3V 5V 24 0...

Page 17: ...paper enters the set but it does not reach the feed sensor in certain time due to slip etc After the picking up cycle if the feed sensor is not on re pick up After re picking up if the feed sensor is not on after certain time it is JAM 0 Even though the paper reaches to the feed sensor the feed sensor is not ON This is an indication that the leading edge of the paper has already passes the feed se...

Page 18: ...4 18 Summary of Product Samsung Electronics Service Manual MEMO ...

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