8-62
Drive Functions
MPH-02, MPB-02, MPD-02
DOK-INDRV*-MP*-02VRS**-FK01-EN-P
Operating principle of position-independent temperature correction:
act. temperature
refer. temperature
corr. value internal
actual position value
P-0-0407, Temp. factor
position-indep.
act. pos. val., corrected
Fig. 8-44:
Position-independent temperature correction
Drive-internal determination of the correction value:
x
k
= P-0-0407 * (P-0-0405 - P-0-0402)
Xk:
correction value, temperature-dependent
P-0-0407:
axis correction temperature factor pos.-independent
P-0-0405:
axis correction actual temperature pos.-independent
P-0-0402:
axis correction reference temperature
Fig. 8-45:
Determining the correction value
The value for
P-0-0407, Axis correction temperature factor pos.-
independent
can be determined by means of calculation or
measurement.
If all data for the formula below can be unequivocally assigned due to the
assembly of the mechanical system, the correction factor can be
calculated.
ref.temp
L
*
0407
-
0
-
P
α
=
P-0-0407:
axis correction temperature factor pos.-independent
α
:
Linear expansion coefficient of the material
L
ref.temp
:material length the temperature expansion of which has to be
compensated (at reference temperature)
Fig. 8-46:
Calculating P-0-0407
mm/0.1K
0.00018
mm
100
*
1/K
0.000018
L
*
0407
-
0
-
P
ref.temp
=
=
=
α
α
:
e.g. 0.000018
1
/
K
, if temperature scaling °C
(default scaling)
L
ref.temp
:
e.g. 100mm (preferred scaling)
Fig. 8-47:
Example for calculating P-0-0407
If it is impossible to calculate the value for P-0-0407 (e.g. if the object of
correction consists of different materials), it has to be measured. A series
of measurements determines the actual position value error of the object
of correction at different temperatures. Depending on the temperature
difference, a straight line can be approximated by means of the
measuring points.
Position-Independent
Temperature Factor
Calculating the Value
Measuring the Value
Courtesy
of
CMA/Flodyne/Hydradyne
▪
Motion
Control
▪
Hydraulic
▪
Pneumatic
▪
Electrical
▪
Mechanical
▪
(800)
426-5480
▪
www.cmafh.com
