Siemens SIMATIC S5 Manual page 159

Input
Module:
The previously entered module number is displayed here,
Axis:
The previously selected axis number is displayed here,
The previously selected dimension is displayed here.
Axis type:
The previously selected axis type ("LINEAR" or "ROTARY") is displayed here.
Description of the input fields
Maximum frequency
This is the highest frequency to be output to achieve the maximum speed in the selected
half or full step mode.
Start/stop frequency (f..):
The maximum frequency at which the stepper motor can startup from a standstill without
losing a step or can brake to a standstill immediately taking into account the load and half
or full step mode.
Rate of freq. increase (a):
a is the slope of the function
f(t) = F(I -e-VT) + F.. => a = F/1
Pulse duration:
This is the width of the pulse per period in microseconds. The pulse duration must always
be less than the period of the maximum frequency.
No. of excitation patterns:
For the stepper motor to move on, it must be excited differently from step to step until it re-
turns to a position corresponding to the initial position. From this position, it can once
again be moved with the same excitation pattern. !n this field, you enter the number of
steps that must be output between two equivalent positions. In the half step mode, this
number is twice as high as in the full step mode.
Polarity:
You select either "positive edge" or "negative edge" as the active edge of the pulse, to
which the power unit reacts. At the same time, the outputs also change their inactive
levels. (=> Part 4 "Functions").
Significance of the function keys
Select the next machine data page.
<Fl >:
Select the previous machine data page.
<F4>:
print out all machine data,
Store all machine data on the destination device.
Return to the basic display without saving the data
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