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ifm
Programming Manual
ecomatmobile
CabinetController (CR0301) Runtime System V05
2016-04-21
ifm function elements
ifm function elements for the device CR0301
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Parameters of the inputs
20969
Parameter
Data type
Description
INIT
BOOL
FALSE
TRUE (edge):
unit is initialised
FALSE:
during further processing of the program
RELOAD
WORD
Value for the determination of the PWM frequency
(→ chapter
Calculation of the RELOAD value
(→ page
DIV64
BOOL
CPU cycle / 64
CHANNEL
BYTE
Number of the PWM output channel
0...3 for the outputs OUT00...OUT03
VALUE
WORD
Current PWM value
permissible = 0...RELOAD
0 = switch-on time 100 %
RELOAD = switch-on time 0 %
CHANGE
BOOL
TRUE:
Adopting new value from ...
• VALUE: after the current PMW period
• DITHER_VALUE: after the current Dither period
FALSE:
the changed PWM value has no influence on the output
DITHER_VALUE
WORD
peak-to-peak value of the dither in [‰]
permissible values = 0...1 000 = 0000...03E8
DITHER_DIVIDER
WORD
Dither frequency = PWM frequency / DIVIDER * 2
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PWM frequency
1529
Depending on the valve type, a corresponding PWM frequency is required. For the PWM function the
PWM frequency is transmitted via the reload value (PWM) or directly as a numerical value in [Hz]
(PWM1000). Depending on the controller, the PWM outputs differ in their operating principle but the
effect is the same.
The PWM frequency is implemented by means of an internally running counter, derived from the CPU
pulse. This counter is started with the initialisation of the PWM. Depending on the PWM output group
(0...3 and / or 4...7 or 4...11), it counts from 0xFFFF backwards or from 0x0000 forwards. If a
transmitted comparison value (VALUE) is reached, the output is set. In case of an overflow of the
counter (change of the counter reading from 0x0000 to 0xFFFF or from 0xFFFF to 0x0000), the output
is reset and the operation restarts.
If this internal counter shall not operate between 0x0000 and 0xFFFF, another preset value (RELOAD)
can be transmitted for the internal counter. In doing so, the PWM frequency increases. The
comparison value must be within the now specified range.
Summary of Contents for Ecomat 100 Mobile CR0301
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