Honeywell 4022, System Manual

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Precision Platform 4022 Series Scanner Components On-screen scanner setup and diagnostics
p/n 6510020208 10/4/07
5-31
A chiller in a closed-loop system can be used to supply coolant to the heads.
One Honeywell chiller can service up to two scanners in parallel.
Supplying the heads with chiller coolant requires connecting hoses from the
chiller to supply and return fittings on the fluid manifold at the cable end
support. A backup system of potable water is also needed to use in the
event of chiller failure.
5.8.1.2. PrecisionPak head environment control devices
The PrecisionPak heads are cooled by an Environment Control Unit (ECU)
coolant-to-air heat exchanger located in each head.
The ECU includes:
•
A coolant-to-air heat exchanger.
•
Two fans with a minimum capacity of 0.85 m
3
/min (30 ft
3
/min).
•
A PCB with a temperature setpoint adjustment potentiometer
(used in controlling head platform temperature utilizing an
external coolant solenoid valve). The PCB uses a thermistor that
monitors platform temperature.
•
An air trim heater controller (used to increase the air temperature
in the head if required). The controller uses a thermistor that
monitors internal head temperature.
•
A controller (used to adjust the heated air wipe unit). The
controller uses a 100 K ohm thermistor mounted in the sheet
guide to control gap temperature. This is not applicable on the
4022-40 Wire Calender scanner model as air wipes and the sheet
guide thermistor are not present.
•
Two heaters, 56 VAC, wired in parallel, 165W total (used to heat
the sheet guides)
•
Hoses and manifolds that deliver cooling fluid.