Kodak 800 SERIES service manual Thermal Dryer Assembly

NovaJet 800 Series Service Manual

The power supply is fused using a 6.3A 250V fast blow type fuse.

The outputs share a common ground which is isolated from earth ground with in the supply itself. Earth ground and DC ground are connected external of the power supply.

The power supply will shut down under overload/short circuit conditions on any output over the full range of input voltage. Overvoltage protection is 20%-30% above nominal for the 24V output.

Thermal Dryer Assembly

To ensure prints are dry for unattended printing, the printer features a thermal (hot air convection) drying system. The system monitors the temperature and humidity in the environment and adjusts the heat to optimize drying time and ensure consistent image quality. The fans blow air past 1200 watt heating elements, quickly drying the media. The dryer effectively dries prints up to 100 sq/ft/hr @ 250% ink saturation. The dryer system easily mounts to the stand assembly. The dryer logic cable connects the dryer to the right leg logic jack. The dryer power cord plugs into the power entry module at the rear of printer.

The thermal drying system is composed of the dryer plenum, logic cable, and Main PWA (humidity and temperature sensors). The dryer typically stays on for approximately 3 minutes following a print job when the Dryer is in the on mode. Auto-Cut Delay is the time set between successive print jobs (dry time between prints).

The Dryer PWA has two thermistors which provide feedback to the Main PWA firmware to raise or lower temperature inside the plenum. The firmware in turn drives the dryer PWA Triac (attached to heatsink) to deliver the current to the two 1200-watt heating elements. The dryer may be turned on, off, or placed into the auto-mode. The maximum temperature obtainable is approximately 52 degrees Celsius. The 60" unit runs a little cooler than the 42" platform due to the additional length of the 1200-watt heating elements (twin 500 to 600 watt elements). The glass fuse on the Dryer PWA will normally fail before an active component due to an overcurrent condition.

Theory of Operation 2-19