Positioning
IP 240
Maximum traversing speed
The encoder pulses acquired by the IP are counted in a counter chip. The current (internal) count is
read once in every module firmware cycle and is then post-processed to form the (external) actual
value.
In order for the IP 240 module firmware to ascertain the direction of movement without any
ambiguity whatsoever, the change in the actual value between two count readouts (t
LZ
) must be
less than the halved final value for the rotary axis (t
LZ max.
·v
max.
<0.5·[final value for the rotary
axis]).
The max. amount of time between two count readouts from the counter chip is computed as
follows:
t
LZ max.
= t
ka1 max.
+t
ka2 max.
+2·t
kom max.
t
ka1 max.
= Maximum processing time for channel 1
t
ka2 max.
= Maximum processing time for channel 2
t
kom max.
= Maximum amount of time needed for a data interchange
In Chapter 12, ”Response Times”, you will find a list of processing/execution times to help you
compute the permissible traversing speed for your application. When the maximum amount of
time is assumed for processing channel 1 and channel 2 and for the data interchange, t
LZ max.
computes to 7.5 ms.
When computing the traversing speed, also refer to the information presented in Section 10.8.2
”Distance values for the switching and signalling ranges”.
10.4.3 Specifying the Axis Type and the Final Value for the Rotary Axis (RUND)
The axis type is specified during configuring using the RUND parameter:
: JU FB 167
NAME
: STRU.POS
:
:
RUND
: KF x
x=0
The channel is configured for a linear axis
x=1
The channel is configured for a rotary axis
If the channel is configured for a rotary axis, the final value for the axis must be entered in data
words DW 48 and DW 49 of the data block. Configuring FB 167 transfers this value to the IP, and it
cannot be changed following configuring.
Permissible range of the final value for the rotary axis: 1 to 9,999,999
0
2
19
2
11
2
3
0
2
18
2
10
2
2
0
2
17
2
9
2
1
0
2
16
2
8
2
0
Binary representation
BCD representation
DL 48
DR 48
DL 49
DR 49
0
2
20
2
12
2
4
10
6
10
4
10
2
10
0
0
10
5
10
3
10
1
Bit
7
6
5
4
3
2
1
0
Bit
7
6
5
4
3
2
1
0
Data
byte
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
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a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
0
2
21
2
13
2
5
0
2
22
2
14
2
6
0
2
23
2
15
2
7
10-16
EWA 4NEB 811 6120-02a