Operation & Installation Manual V12-V6 2010-05-31.doc
31/05/2010
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number of rejected measurements,
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signal strength,
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signal to noise ratio.
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error indications (if there is a reason for)
The flow calculation module prepares data to be used by other modules as:
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the signal output module
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the display module
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the communication module
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the data logging module
2.4.5. The signal output module
The settings described in this paragraph are only available for users with Developer, Factory
and Service rights. The settings are factory set based on customer requirements.
The electronic hardware provides 4 digital outputs: open collector circuits that can be
switched on or off. The physical outputs are marked as output A, output B, output C and
output D. The software of the signal output module determines the variable and the “format”
used to control each physical output. This is set by a number of parameters.
Format means here that an output is either switched “on” or “off” to represent a binary
(logical) value (for example flow direction is “forward” or “reverse”) or the output is used to
transmit a frequency or pulse width modulated signal to represent a numerical value.
In order to present a numerical value as a frequency or as a pulse width modulated signal,
this numerical value must be converted first. The software contains the frequency
synthesizer function and the pulse width modulation function, both are capable to convert
one numerical value, this can be two different values or the same values, as both functions
are independent and may be used at the same time.
The following parameters are used to program the frequency conversion:
frequency output value:
selects the numerical value (variable) to be converted to
a frequency
frequency output 100 % output :
the upper frequency of the normal operating range of
the frequency output (for short: F100%)
frequency output 100 % reference : the numerical value of the variable that will be
converted to a frequency of F100% (for short: Ref100%)
frequency output over range :
in case the numerical value exceeds Ref100%, the
frequency will exceed F100%. This parameter sets a
limitation to the maximum frequency equal to F100% +
the over range percentage (related to F100%).
In addition to the primary frequency signal secondary frequency signals are available,
related to the same variable and having the same frequency but with a phase difference of
90 degrees, 180 degrees or 270 degrees.
The parameters used to program the pulse width conversion are:
PWM output value :
selects the numerical value (variable) to be converted to a
pulse width modulated signal
PWM output frequency :
defines the frequency (and consequently the interval time)
of the pulse width modulated signal
