Siemens SIMATIC S5 Manual page 182

The first display in "test" is the test axis selection display,
Fig, 5/1 8 Test axis selection
Description of the output fields
T EST is entered in the header."1 P247° is displayed in the DEVICE output field.
Significance of the function keys
<Fl >:
Test axis 1. After pressing this key, the program branches to the mode display,
<F2>:
Test axis 2. After pressing this key, the program branches to the mode display.
<F3>:
Test axis 3. After pressing this key, the program branches to the mode display.
The EXIT key returns you to the basic display ("function selection"),
Test
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