HP 1050c Service Manual - Page 297

Functional Overview Snout Wiper Snout wiper is used to clean the ink accumulation that happens on the snout of the pen (vertical corner on the interconnect side) because of wiping operation. This is done to avoid spreading this ink over the interconnect when replacing the pen and generating ink shorts between interconnect pads. Handle and Printable Label The handle is used to remove and install the PHC. Also, the printer uses the handle top surface to print and scan some patterns in order to recognize if: n PHC is present or not. n PHC is new or has been used previously. In addition, there is a built-in mark on the handle (a vertical hole) to calibrate the service station (Scan-axis) if there is a problem and the EEROM is erased. HP DesignJets 1050C and 1055CM Printers Service Manual 10-11