Operation; Dehumidifier Fan Heater Control - Develop ineo+ 6500 Service Manual

7. HT-503 (OPTIONAL)
7.2

Operation

7.2.1

Dehumidifier fan heater control

A. Outline
• The fan heater (HTR3) and the dehumidifier fan/1 (FM3) and /2 (FM4) generate hot airflow inside the LU and
reduce moisture in order to prevent jam of coated paper due to dampness.
• The dehumidifier control has two processes; a dehumidifier fan heater pre-drying and the temperature limit-
ing dehumidification control. The first one (pre-drying) is made with HTR3 , FM3 and FM4. Once the target
temperature rise is achieved, the pre-drying process is finished and further dehumidification control limiting
the temperature is carried out only by HTR3.
• The dehumidification control is carried out according to the temperature inside the tray detected by the
temperature sensor (TEMS), and continued until the target temperature rise is achieved.
• Feeding paper from the LU cannot be made while the dehumidification control being performed. (this can
be allowed by changing DIPSW setting)
B. Dehumidifier fan heater pre-drying control
• The user setting menu has an option to activate pre-drying with the dehumidifier fan heater before printing
every time the upper door is opened/closed.
• When the pre-drying with the dehumidifier fan heater is set not to be activated in the user setting menu, the
pre-drying before printing is carried out if the upper door is opened/closed and a change in remaining
amount of paper is detected.
• HTR3, FM3, and FM4 turn on when 56% or higher ambient humidity is detected by the temp/humidity sen-
sor/1 (TEM/HUMS/1) of the main unit.
• FM3 and FM4 are turned on at regular intervals, and kept on for a specified time period.
C. Triggers for dehumidification control
• When the sub power switch (SW2) is turned on with the dehumidifier fan heater setting set to [Automatic] or
[On (compulsory)], and with the paper type set to coated paper.
• After the upper door is opened/closed with the dehumidifier fan heater setting set to [Automatic] or [On
(compulsory)], and with the paper type set to coated paper.
• When the paper type is changed to coated paper from other paper type with the dehumidifier fan heater
setting set to [Automatic] or [On (compulsory)].
• When the dehumidifier fan heater setting is changed to [Automatic] from [Off (compulsory)], or changed to
[On (compulsory)].
D. Temperature limiting dehumidification control
• After the pre-drying is finished, the HTR3 is turned on or off to keep the target temperature.
Ambient humidity
Lower than 55%
56 to 60%
61 to 65%
66 to 70%
71 to 75%
Higher than 76%
E. Conditions to stop the dehumidification control
• When other than coated paper is selected as the paper type while the control is in progress.
• When the dehumidifier fan heater setting is changed to [Off (compulsory)] while the control is in progress.
26
Theory of Operation Ver1.0 Sep.2006
Target temperature rise in the tray
Not controlled
6°C
7°C
8°C
9°C
10°C