NovaJet 800 Series Service Manual

firmware is unable to read the plenum temperature, main-board tempera- ture, or main-board humidity, the corresponding equals sign (=) will change to a tilde (~). This error condition signifies an internal bus commu- nication failure only. It does not indicate sensor connection or perfor- mance errors.

The Dryer Mode: and Plenum T. items will also modify their display if a dryer component or main-board sensor error is detected. If the dryer circuit board detects an over-temperature condition or if it is disconnected from the printer, Dryer Mode: will indicate “DISABLED” and Plenum T. will indicate “(Hdw. Fault)”. The dryer firmware will shut down the dryer by switching to “OFF” mode, turning the heater power off and turning the fans on automatically. The dryer circuit board will react in a similar fashion by switching to its own “shutdown mode” which turns the heater power off and turns the fans on automatically. This duplicate reaction by hardware is provided in the case where the firmware has lost control. The dryer will remain in this “shutdown” state until power is recycled.

If the firmware detects a Plenum T. sensor error, Dryer Mode: will display “DISABLED” and Plenum T. will display “(T. Error)”. This error can occur if the plenum temperature falls below –10 degrees C or if the firmware is unable to read the plenum temperature for one minute or longer. Typically, a negative temperature indicates a broken connection in the thermistor-to-main-board connection. If unable to read the tempera- ture, the firmware is receiving bad data from the Dallas Bus. The dryer firmware will shut down the dryer by switching to “OFF” mode, turning the heater power off and turning the fans on automatically. The dryer will remain in this “shutdown” state until power is recycled.

Additional information will be displayed if the “F6” panel button is se- lected (second button down on the right side of control panel) and held down. If Dryer Mode: displays “OFF”, “ON”, or “AUTO”, the target heater temperature will be displayed (in degrees C). In addition, if the heater power is on, a “^” character will also be displayed. If Dryer Mode: displays “DISABLED”, the error temperature will be displayed on the Plenum T. line immediately after either “(Hdw. Fault)” or “(T. Error)”. This error temperature value indicates the plenum thermister

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Kodak 800 SERIES service manual Troubleshooting