Festo CiA 402 Manual page 53

4 Setting parameters
6094 : velocity_encoder_factor
h
The object velocity_encoder_factor converts all speed values of the application from speed_units into
the internal unit revolutions per minute. It consists of numerator and denominator.
Index
Name
Object Code
No. of Elements
Data Type
Sub-Index
Description
Access
PDO Mapping
Units
Value Range
Default Value
Sub-Index
Description
Access
PDO Mapping
Units
Value Range
Default Value
Calculation of the velocity_encoder_factor is in principle made up of two parts: A conversion factor
from internal length units into position_units, and a conversion factor from internal time units into user-
defined time units (e.g. from seconds into minutes). The first part corresponds to the calculation of the
position_factor. For the second part, an additional factor is added to the calculation:
Parameter Description
time_factor_v The ratio between the internal time unit and the user-defined time unit.
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. 4.6 Speed factor parameters
The calculation of the velocity_encoder_factor uses the following equation:
velocity_encoder_factor
Festo – GDCP-CMMS/D-C-CO-EN – 1404NH – English
6094
h
velocity_encoder_factor
ARRAY
2
UINT32
01
h
numerator
rw
yes
–
–
1
02
h
divisor
rw
yes
–
–
1
)
OUT
numerator
divisor
) and revolutions at the drive-out
IN
) and movement in
OUT
gear_ratio * time_factor_v
feed_constant
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