Festo CiA 402 Manual page 56

4 Setting parameters
user-defined time units squared (e.g. from seconds
calculation of the position_factor. For the second part, an additional factor is added:
Parameter Description
time_factor_a The ratio between the internal time unit squared and the user-defined time unit
squared.
(e.g. 1 min
gear_ratio Gear ratio between revolutions at the drive (R
(R
feed_constant Ratio between revolutions at the drive-out (R
position_units (e.g. 1 R = 360 degrees)
Tab. 4.8 Acceleration factor parameter
Calculation of the acceleration_factor uses the following equation:
acceleration_factor
The acceleration_factor is also written into the motor controller separated by numerator and denomin-
ator, so it may have to be expanded.
EXAMPLE
First, the desired unit (column 1) and the desired number of decimal places (DP) must be specified,
along with the application's gear ratio and its feed constant (if applicable). The feed constant is then
displayed in the desired positioning units (column 2). Then the desired time unit is converted into the
time unit of the motor controller (column 3). Finally all values can be entered into the formula and the
fraction can be calculated:
Process of calculating the acceleration factor
Units of Feed
acceleration const.
²
mm/s ,
63, 15
1 DP
1 R
mm ²
1/10 /
s OUT
mm ² 631, 5
( / )
10 s
56
2
= 1 min x 1 min = 60 s x 1 min =
).
OUT
nummerator
divisor
Time Constant
mm
1
1
R
2
s
1
60
min * s
1
mm
min
10
60 * 256
256 * s
2 2
into minutes ). The first part corresponds to the
60
/
256
) and revolutions at the drive-out
IN
) and movement in
OUT
gear_ratio * time_factor_a
feed_constant
Gear Equation
1
60 * 256
4 256 min * s
4/5
*
5 1
1
s 2
mm
631, 5
10
Festo – GDCP-CMMS/D-C-CO-EN – 1404NH – English
256 min x s).
Result
shortened
1
min
122880
num: 8192
256 s
div:
mm
6315
10s 2
421