Siemens 6DR55 Series Manual page 37

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SIPART PS2 PA Manual
A5E00127926--05
NOTE
To prevent premature wearing of the fixture by the self--tapping screw
(1.1) next to the display, the following method of mounting the module
cover (1) has proven effective.
1. Turn the screws counterclockwise until you feel them snap into the
thread.
2. Tighten both screws carefully in clockwise direction.
Design and method of operation
35