Siemens SIMATIC S5 Manual page 39

Machine Data and their Structure
Speeds for the various modes are assigned in the machine data record. The speeds must be
selected as follows, depending on the dimensional unit:
in mm/min for metric input,
in 0.1 inches/rein for dimensions in inches or
in degrees/rein for dimensions in degrees
The maximum range of values is 1 to 65000.
The starting point is the maximum speed. This is the speed at which the drive travels when the
pulse generator outputs the maximum frequency to the power unit. This speed and frequency
must be determined exactly from the technical specifications of the drive.
Speed [dimensional unit/rein] = frequency
Example
fmex
Transmission ratio =
Pulses
Positioning resolution =
Maximum-speed [mm/min]
Note
The positioning resolution is directly proportional to the traversing distances and
the speed. To ensure that the distances travelled and the speeds correspond ex-
actly to those selected, the positioning resolution must correspond exactly to
the technical reality.
Minimum speed
The minimum speed
Vmin
[1
=
The value of f~in is determined when the ramp table is generated from the machine data.
Maximum frequency, start-stop frequency and rate of frequency increase.
No speed can exceed the maximum speed.
2-22
positioning resolution . RI
x
— —
30 kHz
1 mm/revolution
— —
500 pulses/revolution
1 mm/500 pulses = 0.002 mm/pulse
= 30000 x 0.002 x 60= 2600 mm/min
is calculated as follows:
I