NovaJet 800 Series Service Manual

NOTE: The carriage housing has been modified from that of the Right Carriage Assembly. The belt strain relief has been removed and the encoder sensor clip has been removed.

The Right Carriage PWA contains the logic and drive circuitry for the firing of the inkjet cartridges. It also establishes an interface path for the optical sensor and paper sensor to communicate with the Main PWA.

The optical sensors receive their inputs from the optical encoder strip and sends this data to the Main PWA. The Main PWA uses this information to determine the horizontal position of the carriage assem- bly so that accurate printing can be established.

The paper sensor circuitry senses for the presence of loaded media. It does this automatically during the start-up and load sequences. It also constantly monitors the media during printing to determine if the media has run out.

If no paper is sensed, the paper sensor sends this information to the Main PWA, which immediately begins an ‘out of paper’ subroutine. This subroutine stops the printer from printing until more media is loaded. NOTE: Space lighting must be at a constant level or the paper sense circuitry will create an error and print operations will cease.

The sensor also checks for the size of the media loaded so it can determine the proper printing parameters.

The Green LED on the Right Carriage and Left Carriage PWA indi- cates the proper drive voltage is available for the driver ICs. It is dim when the printer is idle but becomes bright during printing.

Theory of Operation

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Kodak 800 SERIES service manual Theory of Operation