HP DESIGNJET 3D, Service Manual

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in turn is controlled by the controller board. The following is a list of
actuators:
• Door solenoid – locks the door to the modeling chamber.
• Carrier latches – holds carriers in the material bays.
• Material bay solenoids – engage the motor that feeds filament from
carrier to the liquefier during auto load.
The controller board reads and updates the remaining material information
on the spool e-prom. This is accomplished through a serial interface to the
material bay encryption board. The material encryption board in turn
connects to the e-prom on the carrier/spool via two pogo pins.
The controller board monitors these switches:
• Z limit switches – upper and lower
• X end of travel (EOT) switch
• Y end of travel (ETO) switch
The controller board monitors the following optical sensors:
• X home (BOT) sensor
• Y home (BOT) sensor
• Top of modeling base sensor
Safety Devices
The controller board monitors the following safety devices:
• Chamber T/C alarm – activated for a bad or missing T/C
• Liquefier T/C alarm – activated for a bad or missing T/C
• Head and chamber “snap” switches
• Two main thermal fuses
• Door open switch
• Door latch solenoid
Controller Board Layout
(Figure 4) Shows the layout of the controller board connectors with labels
indicating where each of the functions described previously are connected.
In addition to those functions, the figure shows a reset button, a set of dip
switches, and the LEDs (D1-D3 and D6-D13).