Charge Roller Voltage Correction
Correction for Environmental Conditions
The voltage transferred from roller to drum could vary with the temperature and humidity around the drum
charge roller. The lower the temperature or humidity, the higher the applied voltage required.
The ID sensor measures the effects of ambient conditions, and any small change in drum potential caused
by changes in temperature/humidity is reflected in the amount of toner transferred to the drum.
This measurement is done immediately after the ID sensor pattern for toner density control. After creating
ID sensor pattern [A], another pattern [B] is made. To do this, the LD switches off, the charge roller voltage
drops, and the drum potential is reduced to –600 V. At the same time, development bias returns to –550
V. The drum potential is now slightly higher than the development bias, so only a very small amount of toner
6. Details
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6
Summary of Contents for A-P4
Page 1: ...Model A P4 Machine Code G147 SERVICE MANUAL May 12th 2006 Subject to change...
Page 27: ...Installation Flowchart 1 Installation 26 1...
Page 59: ...3 Reattach the application cover x1 1 Installation 58 1...
Page 65: ...2 Preventive Maintenance 64 2...
Page 72: ...Left Covers 1 Left upper cover A x4 2 Controller cover B x2 Covers and Common Procedures 71 3...
Page 82: ...Laser Unit 81 3...
Page 103: ...5 Cover C x2 6 Gear D x1 7 Lower paper feed unit E x2 x1 3 Replacement and Adjustment 102 3...
Page 128: ...Duplex Unit Duplex Cover Removal 1 Duplex unit cover A x4 Duplex Unit 127 3...
Page 181: ...4 Troubleshooting 180 4...
Page 289: ...Self Diagnostic Test Flow 5 Service Tables 288 5...
Page 306: ...Controller Block Diagram Board Layout 305 6...
Page 319: ...What Happens When a New Unit Is Detected 6 Details 318 6...
Page 367: ...6 Details 366 6...
Page 379: ...MEMO 378...
Page 380: ...MEMO 379...
Page 381: ...MEMO 380...