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The Control Menu provides access to the types of Automatic Control, Mode of Operation, the parameters which
influence the control algorithms and the Soft Start function: Auto Control Mode, Auto/Manual/Off Control, Dead-
band, Autotune, Proportional Band, Integral, Rate (Derivative), Soft Start function and Manual Offset.
5. Control Menu
Auto Control Mode
When the ITC is in AUTO Mode (see AUTO/MANUAL/Off parameter), the choice of
Automatic Control is either PID or ON/OFF Mode.
Auto/Manual/Off
(Mode of Operation)
Determines the type of Control Operation: Automatic, Manual or Off.
Automatic Control: Select Auto. This allows PID or On/Off control.
Manual Control: Select 1 – 100. This is the % power output.
Off: Select 0. This equates to 0% output, which turns off that circuit.
NOTE: The Soft Start function will only engage when the ITC is in AUTO Mode
Autotune
The ITC Autotune function establishes the individual P, I & D (Proportional Band, Integral
& Derivative) control modes. These modes help to bring the process variable to the
setpoint temperature as quickly as possible.
In order to properly calculate the P, I & D modes, the Autotune program requires a 25
degree rise in sensed temperature after initiating the program. If within 30 minutes the
temperature will not reach its setpoint, the Autotune algorithm will be canceled and old
PID values will be used.
Once the Autotune feature is activated, you must not change the menu page until the
Autotune algorithm is completed. Changing the page will cause the Autotune algorithm
to shut down.
The Autotune function is a one-time algorithm set up of the P, I & D control modes.
Should your process variables change significantly, it is suggested to that the Autotune
feature be turned off and then reinitiated.
Deadband
Active ONLY when the ITC is in Auto Mode & under On/Off Control
The temperature range equally divided above & below the temperature set point, where
the controller will not take corrective action.
Example: A setting of “10” for the deadband will result in a deadband that is 5 degrees
above and below the temperature setpoint.
Proportional Band, P
Active ONLY when the ITC is in Auto Mode & under PID Control
The Proportional Band (P), the Integral (I) & Derivative (D) are modes of control that work
in union to bring the process variable to setpoint as smoothly and quickly as possible.
The P, I & D will be automatically established during the Autotune procedure (see above).
Additionally, the P, I & D may all be manually established by the user. Great care should
be taken when manually establishing the P, I & D.
Proportional Band: The temperature range above and below the temperature set point.
Integral, I
(Automatic Reset)
Derivative, D
(Rate)
Soft Start
Will only be available while the Mode of Operation is set to AUTO.
Options are On or Off.
Manual Offset
Only available while the Mode of Operation is set to AUTO & under PID Control
The Manual Offset may be used in conjunction with the PID variables to assist in Tun-
ing the controller. Typically, heat trace applications will not require any Manual Offset
adjustment.
Manual Offset allows the user to preprogram the approximate power output (%) re-
quirement at the setpoint. This has been proven to reduce the time needed to align the
process temperature with the setpoint temperature. As a rule of thumb, relatively light
heating loads will require smaller Manual Offset values.
The Manual Offset is a percentage output with a range of 0 (0%) to 1000 (100%) and a
default of 500 (50%).