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MPH-02, MPB-02, MPD-02
Notes on Commissioning/Parameterization
Minimum Jerk Value
DOK-INDRV*-MP*-02VRS**-FK01-EN-P
Limit Values of the Drive
When parameterizing sequential blocks, the maximum values of the drive
must be taken into account. These values are:
• maximum acceleration capability
• maximum speed (independent of mains voltage)
If blocks are parameterized for which the drive would have to generate
values greater than the maximum values, this will cause an excessive lag
error. With the error message F2028 Excessive deviation the drive will
then signal that it cannot comply with the position command value.
Minimum Values for Acceleration and Jerk
If the acceleration values are too low, this can cause problems.
Therefore, guide values according to the formula below are to be
preferred when determining positioning blocks:
Minimum acceleration value
>
a
cceleratio
n
2
*
x
:
target position of block n
n
x
:
target position of block n+1
n+1
v
:
velocity of block n
n
v
:
velocity of block n+1
n+1
Fig. 7-42:
Minimum acceleration value with sequential block mode (linear)
Note:
The above relationship applies to an infinitely large jerk which
corresponds to a jerk filter that has been switched off (= 0). If a
jerk filter is used, the calculated values have to be doubled in
first approximation. The distance to be run with a block and
the respective velocity are generally fixed by the process. If the
minimum acceleration value calculated with the above guide
value formula already causes the maximum value mentioned
in the previous section to be exceeded, a lower positioning
block velocity must be selected.
If the acceleration values parameterized are too low, this can cause the
parameterized velocity not to be reached. In this case, the so-called
"triangular mode" is used.
Directional Change within a Sequential Block Chain
Note:
If a directional change takes place when changing from
block n to block n+1 of a sequential block, the mode
"Switching at target position with halt" should be used for
block n to reverse the direction without overshoot.
Operating Modes
2
v
elocity
difference
target
position
difference
7-71
(
)
−
2
v
v
=
n
+
1
n
(
)
−
2
*
x
x
n
+
1
n
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