Chapter 88-3The CPU on the DC controller monitors the voltage of the M_TH/S_TH signal to control the fixing heater 1 drive signal (H1DRV) and fixing heater 2 drive signal(H2DRV). These two voltages are generated based on the zero crossing detection signal which is output from the heater control circuit. The CPU controls these twosignals to adjust the fixing heater temperature to the prescribed value.8.2.2.2 Controlling the Fixing Film Temperature 0017-5474iR2022i / iR2025 / iR2030 / iR2018 / iR2022 / iR2018iThis machine performs fixing temperature control according to the fixing heater temperature as mentioned below.1) Warm-up temperature controlUpon receipt of a print command from the DC controller, the fixing heater heats to the temperature below the target paper-present section temperature.2) Paper-present section temperature controlThe fixing heater temperature is adjusted to the target paper-present section temperature according to the combination of the paper size, number of sheets fed,fixing mode, and temperature detected by the fixing main thermistor.3) Sheet-to-sheet temperature controlThe fixing heater temperature is held relatively below the target paper-present section temperature to prevent the paper-absent section temperature from risingbetween sheets.4) Down sequenceThe temperature may detect an abnormally high temperature during continuous printing. If the sub-thermistor detects a temperature equal to or higher than 275deg C, the sheet-to-sheet distance is increased to prevent the paper-absent section temperature from rising. If the sub-thermistor detects a temperature equal toor lower than 220 deg C in the down sequence, normal control resumes.5) Cooling modeIf printing is performed using wider sheets (*1) after printing is performed using narrower sheets in the continuous print mode, fixing offset may occur due tothe difference in temperature between the edge and center. If the sub-thermistor detects a temperature equal to or higher than 130 deg C, paper feed and printingstop to prevent the temperature from rising at the edge. If the sub-thermistor detects a temperature equal to or lower than 130 deg C or two or more minutes lapse,normal control resumes.*1: The large size is a paper of which the width is 10 mm larger than the previous job.8.2.2.3 Target Temperatures by Mode (iR2030/iR2030i) 0017-5475iR2030This machine controls the fixing temperature according to the "media type" selected in the user mode and the "target temperature" set in the "special mode."The correspondence between each mode and target temperature is as follows:T-8-2*1: Target fixing temperature at startup. When the initial temperature of the fixing unit is high, the target temperature is lowered. In the continuous copy mode, thetarget temperature is lowered in 5 deg C steps.*2: Number of sheets controlled at the initial target temperature. If it is exceeded, the target temperature is lowered. The prescribed number of sheets varies withthe paper size.8.2.2.4 Target Temperatures by Mode (iR2025/iR2025i) 0018-0262iR2025Fixing mode Paper type Target initial fixingtemperature (*1)Initial number of sheets(*2)ConditionNormal Plain paper (colored paper/recycled paper/label sheet (64-80g/m2)206 deg C 1-12 (A4/LTR) Special Mode P: Off196 deg C 1-12 (A4/LTR) Special Mode P: Medium186 deg C 1-12 (A4/LTR) Special Mode P: HighRough Paper Lo Heavy paper 1(81-90 g/m2)211 deg C 1-12 (A4/LTR)Heavy paper 2(91-105g/m2)Rough Paper Heavy paper 3(106-128g/m2)220 deg C 1-25 (A4/LTR)Super rough paper Bond paper 220 deg C 1-100 (A4/LTR) Bond SP. FIX. Mode: OFFSuper rough paper Hi Bond paper 220 deg C 1-100 (A4/LTR) Bond SP. FIX. Mode: ONPostcard Postcard 220 deg C 1-12 Fix. Unit Offset: OFFPostcard H Postcard 220 deg C 1-7 Fix. Unit Offset: 1 or 2Envelope Envelope 220 deg C 1-10OHP OHP 186 deg C 1-12 (A4/LTR)
