Image Transfer and Paper Separation
D017/D018/D019/D020 6-68
SM
1. When the CPU receives the image writing start signal, the CPU instructs the high
voltage supply board to 10
μ
A (low transfer current level) to the roller. This
prevents any positively charged toner on the drum surface from transferring to the
transfer roller.
2. At a certain time after the low transfer current has been supplied to the roller, an
appropriate current is applied to the roller to transfer the toner to the paper.
3. After the trailing edge of the paper has passed through the roller, transfer current turns
off. In multiple copy mode, the transfer current shifts again to the low transfer current.
The transfer current (high transfer current level) depends on the paper feed station, paper
width, and the temperature in the machine.
Example: Temperature = 15 °C to 24 °C
Paper Width
Paper Tray /
By-pass Tray
(Normal)
Duplex (2nd Side)
By-pass Tray
(Thick) / 2nd
Paper Tray
(Special Paper)
A3/11” x 17”,
A4/8.5 x 11”sideways
14
μ
A 10
μ
A 14
μ
A
B4
13
μ
A 12
μ
A 15
μ
A
A4/11” x 8.5 lengthwise,
A5/5.5 x 8.5 sidewise
13
μ
A 16
μ
A 17
μ
A
A5/8.5 x 5.5 lengthwise
and less
16
μ
A 16
μ
A 20
μ
A
The transfer current can be adjusted using SP2301, except for the low transfer current.
Be careful when increasing the transfer current. This might cause a ghosting effect, in
which part of the image at the top of the page is repeated lower down the page at a lower
density. It may also damage the OPC drum in the worst case.
6.12.3 TRANSFER ROLLER CLEANING
If the paper size is smaller than the image, or if a paper jam occurs during printing, toner
may be transferred to the roller surface. To prevent the toner from transferring to the back
side of the printouts, the transfer roller requires cleaning before the next printing run.
During transfer roller cleaning, the high voltage supply unit supplies a negative cleaning
Summary of Contents for Aficio MP 2550B
Page 1: ...D017 D018 D019 D020 SERVICE MANUAL 003320MIU ...
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Page 3: ...D017 D018 D019 D020 SERVICE MANUAL ...
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Page 5: ...D017 D018 D019 D020 SERVICE MANUAL 003320MIU ...
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Page 32: ......
Page 33: ...INSTALLATION ...
Page 34: ......
Page 120: ......
Page 121: ...PREVENTIVE MAINTENANCE ...
Page 122: ......
Page 130: ......
Page 131: ...REPLACEMENT AND ADJUSTMENT ...
Page 132: ......
Page 201: ...TROUBLESHOOTING ...
Page 202: ......
Page 238: ...Self Diagnostic Mode D017 D018 D019 D020 4 36 SM Self Diagnostic Test Flow Chart ...
Page 246: ...Image Problems D017 D018 D019 D020 4 44 SM 4 5 2 CHECKING IMAGES WITH THE TRIMMING PATTERN ...
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Page 263: ...SERVICE TABLES ...
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Page 304: ...SP3xxx D017 D018 D019 D020 5 40 SM 5 4 SP3XXX There are no Group 3 SP codes for this machine ...
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Page 489: ...DETAILED SECTION DESCRIPTIONS ...
Page 490: ......
Page 569: ...SPECIFICATIONS ...
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Page 583: ...LARGE CAPACITY TRAY PS500 B391 ...
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Page 607: ...1000 SHEET FINISHER SR790 B408 ...
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Page 635: ...BOOKLET FINISHER SR3000 B793 ...
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Page 640: ......
Page 643: ...Covers SM 3 B793 Booklet Finisher B793 3 Remove the upper left cover C ...
Page 657: ...Folder SM 17 B793 Booklet Finisher B793 6 Remove a connector 7 7 Remove 2 screws 8 ...
Page 658: ...Folder B793 18 SM 8 Remove the staple tray 9 9 Remove the guide 10 2 screws ...
Page 701: ...PAPER TRAY UNIT PB3030 D331 ...
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Page 729: ...FAX OPTION TYPE 3350 D361 ...
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Page 917: ...Fax Communication Features SM 183 D361 Fax Option Type 3350 D361 ...
Page 925: ...ARDF DF3030 D366 ...
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Page 957: ...1 BIN TRAY BN3030 D367 ...
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Page 967: ...BRIDGE UNIT BU3020 D368 ...
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Page 979: ...DUPLEX UNIT AD3000 D369 ...
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Page 994: ...Electrical Component D369 8 SM 4 Duplex transport motor B x 2 ...
Page 1003: ...BYPASS TRAY BY3000 D370 ...
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Page 1010: ...Tray D370 2 SM 2 Remove the pins A x 1 each 3 By pass tray B x 1 ...
Page 1015: ...Feed SM 7 D370 Bypass Tray BY3000 D370 6 Separation pad D spring x 1 ...
Page 1019: ...INTERCHANGE UNIT TYPE 3350 D371 ...
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Page 1031: ...500 SHEET FINISHER SR3050 D372 ...
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Page 1058: ...Overview D372 20 SM No What Happens sure that the stapler is at its home position ...
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Page 1103: ...PRINTER SCANNER OPTION D383 ...
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Page 1136: ...Scanner Service Tables D383 6 SM Compression Notch Assignment ...
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Page 1143: ...INTERNAL SHIFT TRAY SH3010 D385 ...
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