Delphin ProfiMessage, Hardware Manual

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Profi Message
Dead zone : Activates the dead zone of the control deviation (xd). Specify the zero
point of the dead zone with Zero point . The entry field Width contains the max-
imum deviation from the zero point of the dead zone, within which the control devi-
ation is set to 0.0.
Output limitation : This option allows the value range of the manipulated variable to
be limited to values larger than -100% or smaller than +100%. The cut term of the
manipulated variable can optionally be fed back to the second D term of the con-
troller.
4.7.15 Pulse width modulation (PWM)
This software channel generates a square signal with a variable frequency and
variable pulse-pause ratio. The pulse-pause ratio is determined by the source.
Frequency/period
:
Enter either a fixed frequency or time for the period of the fundamental oscillation
or name a channel that provides the appropriate value.
Duty cycle
Lower / upper limit : Set here the minimum and maximum values for the pulse-
pause ratio.
A pulse-pause ratio of 0% means that the PWM output is permanently switched
off. A pulse-pause ratio of 100% means that the PWM output is permanently
switched on. The range of source values is limited to the specified range.
4.7.16 Calculation channel
This software calculates the input mathematical formula. Any number of sources
can be linked within the formula. Each source is represented by a variable that can
assume either a constant value or the value from the specified channel.
Method
1. Set the required variables with Add variable .
A variable named var0 is created by default, but its name can be changed.
2. Set whether the variable is to have a constant value ( Manual value ) or
whether the value is to be obtained from a channel ( Channel ).
3. Enter the formula expression in the field Formula .
Restrictions on variable names
1. The first character must be alphabetic (a...z/A...Z).
The subsequent characters must be alphanumeric (letters a...z/A...Z or num-
bers 0..9) or an underscore (_).
2. Variable names must be unique (no repeat names in different channels).
3. A distinction is made between upper and lower case letters.
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Delphin Technology AG
Dezember 2015
Profi Message Manual