Siemens SIMATIC PG 720, Manual

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3
3-14
PG 720 Programming Device
C79000-G7076-C720-02
3.4 Trackball
The trackball is a pointing device for cursor control and menu selection in
many programs that support mouse operation. By moving the trackball, the
cursor can be positioned anywhere on the screen.
By pressing the left-hand button, you set a marker. The function of the
right-hand button depends on the particular application you are using. You
can select objects or items in a menu and start functions with the trackball.
The trackball is in a roller housing which normally prevents dust collecting
on the ball or transmission mechanism. Nevertheless, you should clean the
trackball at regular intervals.
Cleaning the trackball:
1. Switch off your programming device.
2. Remove the cover of the trackball housing by turning it
counter-clockwise, for example by inserting tweezers or a similar tool
into the holes in the ring.
3. You can now take the trackball out of its housing.
4. Wash the trackball in a solution of tap water and mild cleansing agent.
5. Blow any residual dust out of the trackball housing.
6. Dry the trackball and return it to its housing.
7. Replace the cover and tighten it by turning it in a clockwise direction.
Trackball
Cleaning the
Trackball
Getting to Know the PG 720