CLS200 Series User’s Guide
Chapter 4: Setup
83
Heat or Cool Output Filter
Dampen the response of the heat or cool output. The output responds to a step change by going to
approximately 2/3 of its final value within the number of scans you set here. A larger value results in
a slower, or more dampened, response to changes in the process variable.
ALARM
01 HEAT CONTROL
FILTER ? 3
Selectable values:
0
to
255.0
disables the output filter.
Spread
For a loop using on/off control, the spread is the control hysteresis. This determines the difference
between the point at which a heat output turns off as the temperature rises, and the point at which it
turns back on as the temperature falls.
For a loop using PID control, the spread determines how far the process variable must be from the
setpoint before the controller can switch from heating to cooling. A loop will not switch from heat to
cool or vice versa unless the process variable deviates from setpoint by more than the spread.
When the loop is using PID control and the spread is set to
0
, the PID calculation alone determines
when the heat or cool output should be on.
ALARM
01 SPREAD ?
5
Selectable values:
0
to
255
,
25.5
,
2.55
,
.255
, or
.0255
, depending upon the
DISP FORMAT
setting.
Restore PID Digital Input
To enable the sensor failure recovery feature, select a digital input at this parameter. If the specified
input is held low when a thermocouple fails, the loop returns to automatic control after the
thermocouple is repaired.
ALARM
01 RESTORE PID
DIGIN ? NONE
Selectable range:
NONE
(disable the sensor failure recovery feature),
1
to
8
.
