Operation & Installation Manual V12-V6 2010-05-31.doc
31/05/2010
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PWM output 100% reference : defines the upper limit of the normal range of the numerical
value to be converted to a pulse width modulated signal
PWM output over range :
defines the maximum value of the numerical value to be
converted to a pulse width modulated signal. This
maximum numerical value of the selected variable will be
converted to a signal having a duty cycle of 100 %
clip negative values to zero:
for example in case of reverse flow, the numerical value of
the flow will be negative. This parameter offers the option
(option “off”) to ignore the sign and have the absolute value
of a numerical value transmitted as a frequency or pulse
width modulated signal. The other option (“on”) will disable
the frequency signal and the pulse width signal in case of a
negative numerical value
Each of the digital outputs A, B, C and D are programmed by means of three parameters:
Mode select:
this parameter defines the source that controls the status (on/off)
of the physical output. The options are:
No output :
output is not used
Binary output :
output is directly controlled by a boolean variable (or logical
value: on/off)
Frequency phase 0 :
output is controlled by the primary frequency signal (the result
of the conversion)
Frequency phase 90 : output is controlled by the secondary frequency signal with
phase 90degrees
Frequency phase 180 : output is controlled by the secondary frequency signal with
phase 180 degrees
Frequency phase 270 : output is controlled by the secondary frequency signal with
phase 270 degrees
PWM :
output is controlled by the result of the conversion to a pulse
width modulated signal
PWM inverted :
output is controlled by the result of the conversion to a pulse
width modulated signal, but signal levels (on /off) are
inverted.
In case two outputs are programmed as frequency output, one being the primary frequency
having a phase of 0 degrees and one being a secondary frequency having a phase of 90
degrees the parameter “Flow direction indication” can be used to program the secondary
frequency phase to be direction dependant. This means the phase will be 90 degrees in case
of positive flow direction and 270 degrees in case of negative flow direction (option automatic
flow direction indication). Otherwise the phase of the secondary frequency will always remain
90 degrees, irrespective of flow direction (option no flow direction indication).
The parameter “Status select” is relevant in case the option “Binary output” is selected for
the parameter : “Mode select” . The parameter “Status select” defines the variable that will
control the status of the physical output being programmed.
The parameter “Bit mask” allows to define the bit pattern (mask) of a 32-bit word. This word
can be used to select specific bits from another 32-bit word, representing the variable
selected with the parameter “Status select”. The bits of this variable, corresponding to the
bits in the mask that have the value “1” are selected to control the output. In case multiple
bits are selected the selected bits are combined with a “or” function in order to obtain a
single binary value. As an example: this function can be used to combine different alarms
represented by separate bits in a 32-bit word to output a single external alarm signal.
