171
ifm
Programming Manual BasicController relay CR0431 v03.03.00
05 / 2018
ifm function elements
ifm function elements for the device CR0431
PERIOD
8122
Unit type = function block (FB)
Unit is contained in the library
ifm_CR0431_Vxxyyzz.LIB
Symbol in CODESYS:
>
Description
15850
PERIOD measures the frequency in [Hz] or the period time (cycle time) in [µs] or the phase shift in [°]
on the specified channel, depending on the set operating mode:
MODE
dec | hex
Description
0
00
no measurement
14
0E
Frequency measurement
Count the positive edges for a certain time.
19
13
Period duration measurement (better replace by MODE = 20!)
Measure the time interval between two positive edges.
Specify the average value over a certain number of periods.
20
14
Period duration and ratio measurement
Measure the time interval between two positive edges.
Specify the average value over a certain number of periods.
25
19
(LZS version 03.02.zz or higher)
Phase shift (0...359°) between channel A and channel B of an input channel pair
(message makes only sense if no great jumps > 179° can occur in the system)
.
The operating mode should not be changed during operation.
If MODE=19 or MODE=20 or MODE=25:
permissible input frequency = 0.1...3 000 Hz
If the load is too high the cycle time can get unacceptably long.
→ chapter
Performance limits of the device
(
14888
NOTE
In case of higher frequencies (higher than those guaranteed by
ifm
) the following problems may occur:
The switch-on and switch-off times of the outputs become more important.
Undue heating of the components may occur.
The influences mentioned above depend on the components used in the individual case.
These possible influences cannot be exactly predicted.
Summary of Contents for BasicController CR0431
Page 228: ...228 10 Notizen Notes Notes...
