SCS LABCOTER 2, Operator'S Manual

Page: 60 / 153

Rev 37 Operator’s Manual OM-610-1002-1
page 52 SECTION 6 MAINTENANCE PDS-2010
dPOS - Decimal Point Position
This parameter, applicable only if a linear input is fitted, defines the position of the decimal point in
values of the process variable, set point, alarm levels, and recorder output as follows:
VALUE DECIMAL POINT POSITION
0 XXXX
1 XXX.X
2 XX.XX
3 X.XXX
Filt - Input Filter Time Constant
The controller input is equipped with a digital filter that is used to filter out any extraneous impulses on
the process variable. This filtered process variable is used for all process variable dependent functions.
The time constant for this filter may be adjusted in the range 0.0 seconds to 100.0 seconds in .5 second
increments.
NOTICE: If this parameter is set to an excessively high value, the control quality may be
significantly impaired. Choose a value that is sufficiently large to attenuate stray noise on the
process variable signal, but no larger.
Inhi - Alarm Inhibit
This inhibits an alarm at power-up, or if a controller set point is switched, until that alarm goes inactive.
The alarm operates normally from that point onwards.
InPt - Input Range
This is the overall input range and type as selected by the Inpt parameter in Configuration Mode.
LAEn - Loop Alarm
This is a controller parameter; it is the means by which the user can enable or disable the loop alarm. The
loop alarm is a special alarm that detects faults in the control feedback loop by continuously monitoring
process variable response to the control output(s). The loop alarm can be tied to any suitable output.
When enabled, the loop alarm repeatedly checks if the control output(s) are at the maximum or minimum
limit. If an output is at the limit, an internal timer is started. Thereafter, if the high output has not caused
the process variable to be corrected by a predetermined amount 'V' after time 'T' has elapsed, the loop
alarm becomes active. Subsequently, the loop alarm mode repeatedly checks the process variable and the
control output(s). When the process variable starts to change value in the correct sense or when the output
is no longer at the limit, the loop alarm is deactivated.
OFFS - Process Variable Offset
This parameter is used to modify the actual process variable value (measured at the Controller’s input
terminals) in the following manner:
Offset Process Variable Value = Actual Process Variable Value + Process Variable Offset Value.
OPuL - Output 1 Power Limit
This parameter is used to limit the power level of Output 1 and may be used to protect the process being
controlled. If no protection is required, this parameter may be set to 100%. The parameter may be
adjusted between 0% and 100%.