Process variable offset - word parameter 26, Scale range maximum - word parameter 12, Scale range minimum - word parameter 11 – West Control Solutions N6600 User Manual
Page 46: Decimal point position - word parameter 18, Input filter time constant - word parameter 25, Output parameters, Output power value - word parameter 3
4.4.1.2 PROCESS VARIABLE OFFSET - Word Parameter 26
This word parameter may be modified/interrogated. It modifies the actual process
variable value (as measured at the Controller’s input terminals) in the following
manner:
Modified PV value = Actual PV value + process variable offset value
The modified PV value is limited by Range Maximum and Range Minimum and is
used for display and alarm purposes and for recorder outputs.
NOTE: This parameter value should be selected with care. Any
adjustment to this parameter is, in effect, an adjustment to the
Controller’s calibration. Injudicious application of values to this
parameter could lead to the displayed PV value having no
meaningful relationship to the actual PV value.
4.4.1.3 SCALE RANGE MAXIMUM - Word Parameter 12
This Read Only word parameter indicates the maximum process input value.
4.4.1.4 SCALE RANGE MINIMUM - Word Parameter 11
This Read Only word parameter indicates the minimum process input value.
4.4.1.5 DECIMAL POINT POSITION - Word Parameter 18
This Read Only word parameter indicates the input range decimal point position.
4.4.1.6 INPUT FILTER TIME CONSTANT - Word Parameter 25
This word parameter may be modified/interrogated. The Controller input is
equipped with a digital filter which is used to filter out any extraneous impulses on
the process variable. This filtered PV is used for all PV-dependent functions
(control, alarms etc.). The time constant for this filter may be adjusted in the range
0.0 seconds (filter OFF) to 100.0 seconds in 0.5 second increments. The default
setting is 2.0 seconds.
CAUTION: If this parameter is set to an excessively high value, the
control quality may be significantly impaired. The value chosen
should be sufficiently large to attenuate stray noise on the process
variable signal but no larger.
4.4.2 Output Parameters
4.4.2.1 OUTPUT POWER VALUE - Word Parameter 3
The value of this word parameter may range between 0% and 100% (for a
single-output Controller) or –100% and 100% (for a dual-output Controller). If
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PM-0075