BECKHOFF AX2000 PROFIBUS DP communication profile - Manual (Page 27)

4.2.5.3 PNU 1785: motion task type
Bit Value Meaning
0
0 The position value that is given is evaluated as an absolute position.
1
The position value that is given is evaluated as a relative traversing distance.
The two following bits then determine the type of relative motion.
1
0
If Bit 1and Bit 2 are set to 0 and Bit 0 set to 1, then the relative motion task is performed
according to the “InPosition” bit.
1
The new target position is given by the old target position plus the traversing distance.
Bit 1 has priority over Bit 2.
2
0
If Bit 1and Bit 2 are set to 0 and Bit 0 set to 1, then the relative motion task is performed
according to the “InPosition” bit.
1 The new target position is given by the actual position plus the traversing distance.
3
0 no following task available
1 There is a following task, but it must be defined through parameter O_FN, PNU 1788
4
0 Change over to next motion task, with braking to 0 at the target position.
1
Change over to next motion task, without standstill at the target position.
The type of velocity transition is determined by Bit 8.
5
0 Change over to next motion task, without evaluating inputs.
1 A following motion task is started by a correspondingly configured input.
6
0
Start the next motion task by Input State = low or if bit 7 = 1after the delay set in
PNU 1789.
1
Start the next motion task by Input State = high or if bit 7 = 1after the delay set in
PNU 1789.
7
0 The next motion task is started immediately.
1
The next motion task is started after the delay time set by PNU 1789 or, if Bit 6 = 1, previ-
ously by a corresponding input signal.
8
0
Only for following motion tasks and Bit 4 = 1: from the target position for the previous moti-
on task onwards, the velocity is altered to the value for the following motion task.
1
The change of velocity is made so that the velocity at the target position of the previous
motion task matches the value given for the following motion task.
9
- reserved 10
11
12
0
Accelerations are calculated according to the run-up/acceleration and run-down/braking ti-
mes for the motion task.
1 the deceleration/aceleration ramps are interpreted in mm/s²
13
0 The target position and target velocity of a motion task are interpreted as increments.
1
The target position and target velocity are recalculated as increments before the start of
the motion task. The parameters PGEARI and PGEARO are used for this purpose.
14
0 The programmed velocity is used as the velocity for the motion task.
1
The velocity for the motion task is determined by the voltage present on analog input 1at
the start of the motion task.
15 - reserved
4.2.5.4 PNU 1783: acceleration time
This parameter defines the total time or rate (depending on the type of units selected for acceler-
ation) to reach the target velocity for the motion task.
4.2.5.5 PNU 1784: acceleration jolt limiting
This parameter defines the form of the acceleration ramp.
If a value
¹ 0 is entered here, then a sin²-ramp (S-curve) is used to reach the target velocity.
To employ sine²-ramps, the configuration variable SPSET has to be set to 2 (via the ASCII-channel
or the ASCII-terminal in the setup software) and to be saved.
PROFIBUS for AX2000/2500 27
BECKHOFF
12/05
Using the parameter channel (PKW)