West Control Solutions N8100 - Manual (Page 31)

3.3 INDIVIDUAL PARAMETERS
The individual parameters and how they may be interrogated/modified are
described below. Unless otherwise stated, the {DATA} element will follow the
standard five-digit format and the decimal point position must be correct for the
new value to be accepted and for modification to occur.
3.3.1 Input Parameters
O054-3 3-5
59125
Parameter Identifier Description
Process
Variable
M Read (Type 2 message) Only; If out of range, {DATA} will
contain <??>0 (over-range) or <??>5 (under-range).
Process
Variable
Offset
v May be read (Type 2 message) or modified (Type 3/Type 4
message sequence). Modifies actual process variable
value (as measured at the input terminals):
Modified PV value
= Actual PV value + PV offset value
Modified value is limited by Range Maximum and Range
Minimum and is used for display/alarm purposes and for
recorder outputs. Choose this value with care. In effect, it
modifies the Controller’s calibration. Lack of care could
result in the displayed PV value having no meaningful
relationship to the actual PV value.
Scale
Range
Max.
G Adjustable only on DC inputs. May be read (Type 2
message) or modified (Type 3/Type 4 message sequence).
Decimal point position is as for the input range. If less than
Scale Range Min. Value, sense of input is reversed.
Scale
Range
Min.
H Adjustable only on DC inputs. May be read (Type 2
message) or modified (Type 3/Type 4 message sequence).
Decimal point position is as for the input range. If greater
than Scale Range Max. Value, sense of input is reversed.
Scale
Range
Decimal
Point
Q Adjustable on DC inputs only. May be read (Type 2
message) or modified (Type 3/Type 4 mesage sequence).
Defines the decimal point position:
0 = abcd
1 = abc.d 2 = ab.cd
3 = a.bcd
Input
Filter
Time
Constant
m May be read or modified using a Type 2 message or a
Type 3/Type 4 message sequence.