HP 2000CP 2500CP - Manual (Page 327)

10-8 Functional Overview HP DesignJet CP Series printers
Mechanical Interface Sensors
D Media Sensor: Detects if the media is loaded or not.
D Pinch wheel Sensor: Detects if the position of the pinch arm is up or
down.
D Service Station Sensor: Senses the position of the service station
assembly.
D Primer Sensor: Senses the position of the primer assembly.
D Elevator Sensor: Senses the position of the elevator assembly.
D Valve Sensor: Four mechanical micro-switches sense the installation of
the reservoir valves in the refill assembly.
D Refill Sensor: Senses the two extreme positions of the refill assembly.