Honeywell 4022, System Manual

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Precision Platform 4022 Scanner Site Preparation
10/4/07 p/n: 6510020208 2-18
2.12.1.3. Head purge air
When power to the system is off with the heads in the offsheet position, it
is possible for internal pressure changes due to temperature variations
inside the head to result in entry of moisture and mill air. To prevent this,
an air purge fitting bleeds air into the head continuously, preventing entry
of outside air.
Air must be kept flowing to the heads when they are in the offsheet
position.
2.12.1.4. Sheet guide temperature control
The sheet guides are heated with embedded resistive heaters. The
embedded sheet guide heaters are on-off controlled and can be run in
three modes selected by a jumper W1 on the power track termination
board (see Table 2-5).
Table 2-5 Sheet Guide Heater Jumper Setting
Sheet Guide Heater Configuration W1 Jumper Setting
Sheet Guide Heaters Always On W1:A
Sheet Guide Heaters Only On when Heads Parked Offsheet W1:B
Sheet Guide Heaters Always Off None
On the 4022-30 and 4022-31 scanner models, the sheet guides are further
heated with heated air wipes. The temperature of the heated air wipes is
controlled by the second proportional controller mounted on the top of
the ECU with the temperature measured by a thermistor embedded in the
sheet guide. Note that this is not applicable for the 4022-40 scanner model
as it does not have heated airwipes or an embedded thermistor in the
sheet guides. See Table 2-6 for controller settings.
Table 2-6 Air Wipe Heater Control Settings
Controller Setting Temperature (°F) Temperature (°C)
1 85°F 29°C
2 99°F 37°C
3 113°F 45°C
4 127°F 53°C