POSIDRIVE
®
FDS 4000
STÖBER
ANTRIEBSTECHNIK
10. Positioning Control
17
Example 2:
Three fixed positions are always traversed in the
same order (
pick and place
).
Solution:
J10
,
J20
,
J30
=Destination specification
J11=J21=J31
=
1:absolute
J16
=2,
J26
=3,
J36
=1 (chaining)
J17=J27=J37
=
0:posi.step
Ö
The movements are triggered by the rising edge of the
posi.step
signal.
Example 3:
A conveyor belt is to stop after exactly 100 mm
following a sensor signal.
Solution:
J11
=
2:endless positive
J16
=2
(Next block no. 2)
J17
=
3:posi.next
(Next start)
J20
=100 mm
J21
=
0:relative
Ö
The
posi.start
signal starts process block no. 1. The drive
continues to run until the rising edge of the
posi.next
signal
after which a branch is made to process block no. 2. When
posi.next
is connected to BE3, the reaction occurs without
a delay time. If the
J17
=
3:posi.next
setting is not made,
posi.next
is ignored! Cf. example 4.
Example 4:
Positioning of a shelf handling device. The exact
destination position is specified by a light barrier
which is triggered briefly at each shelf. Until just
before the destination, the signals of the light
barrier must be ignored. We will assume that the
destination is located between 5.1 m and 5.4 m.
Solution:
The approximate position is traveled to with block no. 1:
J10
=5.1m
(Approximate position)
J11
=
1:absolute
J16
=
2
(Next block no. 2)
J17
=
2:no stop
(Next start)
Posi.next
is activated with block 2 (
J27
):
J20
=5.4 m
(Maximum position)
J21
=
1:absolute
J26
=
3
(Next block no. 3)
J27
=
3:posi.next
(Next start)
The braking distance is defined in block 3:
J30
=0.05 m
(Braking distance)
J31
=
0:relative
Ö
Process block no. 1 is started with
posi.start
. Just before
the probable destination and without an intermediate stop,
a switch is made to process block no. 2 where the
posi.next
signal is armed. Process block no. 3 is triggered
with
posi.next
, and the braking distance specified in
J30
is
executed. If the
posi.next
signal fails to appear (e.g., light
barrier is defective), the drive remains stopped in position
J20
.
Tips:
•
An operational status of
17:posi.active
indicated on the
display means that no process block and no chain of
process blocks (i.e., sequential program) is being executed
at the moment. The drive is under position control. The
posi.start
and
posi.step
signals have the same effect here.
•
The inverter assumes the basic state "
17:posi.active
" when
the enable is turned off and on.
•
The "
17:posi.active
" state can also be output on binary
outputs or relay 2.
10.9
Simple examples
Without the option board, 5 digital inputs are available. Of
these, BE4 and BE5 are required for the connection of the
encoder. Some examples of how the remaining three inputs
can be used are listed below:
Example 1:
Belt drive (i.e., endless movement). Four different
feed lengths are traversed relatively.
Solution:
BE1: RV-select0 (
F31
=1)
BE2: RV-select1 (
F32
=2)
BE3: posi.start (
F33
=19)
BE1
BE2
Block
Process Block Parameter
0
0
1
J10, J12, J13, J14
1
0
2
J20, J22, J23, J24
0
1
3
J30, J32, J33, J34
1
1
4
J40, J42, J43, J44
Ö
The traversing method (e.g.,
J11
,
J21
,
J31
and so on)
remains set to "
0:relative
" for all blocks. The selected
process block is indicated in
I83
.
Example 2:
Linear axis with end stops. Two fixed positions
are traversed absolutely.
Solution:
BE1: RV-select0 (
F31
=1)
BE2: posi.start (
F32
=19)
BE3: ref.input (
F33
=23)
BE1
Position
Process Block Parameter
0
1
J10, J12, J13, J14
1
2
J20, J22, J23, J24
Ö
The traversing method (
J11
and
J21
) for both process
blocks is "
1:absolute
." After power-on, reference point
traversing is automatically executed by
I37
=1 with the first
posi.start
command. The reference switch must have the
characteristics shown in example 1 of chapter 10.6.
Example 3:
Belt drive (endless movement) with stop at pulse
(i.e., defined braking distance).
Solution:
BE1:
posi.start
(
F31
=19)
BE3:
posi.next
(
F33
=20)
J11
=
2:endless positive
J17
=
3:posi.next
J20
=
...(braking distance)
Ö
We recommend applying the
posi.next
signal to BE3
(
F33
=20) so that the delay time of 4 msec is omitted.
Evaluation of
posi.next
is activated with
J17
=3.
For additional details on
posi.next
, see chapter 10.8 (chaining
of process blocks).
Posi.next
signal
Posi.Next
Signal
Fahrsatz 2
Fahrsatz 3
Fahrsatz 1
