Omega CN616TC1, User Manual

Note !! Only the number of segments set in function [74] are allowed to
be set. After last segment is saved the unit segment setup will advance to
the next zone. This way all segments are set in sequence. Out of se-
quence segments can be set by returning to function [75] after saving
each segment.

6.8.2-20

Function [02] to [20]

Set Segment 02 to 20

follow the same procedure as Function [01]

6.9    Function [76] Set  Autotune

Function [76] does not control any other function
On entering function [76] the function display shows 76.
The zone display shows zone 1.
The upper display shows the current Autotune setpoint.
By advancing the flashing digit the operator can scroll through the top
display and the zone display and set the Autotune setpoint & zone.
To increment the flashing digit press the button
To advance to the next digit with press the button
To save the settings and return to function [70]  press the button

6.10  Function [77]

Run Autotune

The PID control constants that are the same for all zones programmed
for PID Mode. Autotuning can be done on any one zone selected for the
Autotuning.  The system parameters are measured during autotuning by
supplying full power output to the system until the autotuning setpoint is
reached, then the output power is switched OFF allowing he tempera-
ture to overshoot and then drop down freely back to the autotuning
setpoint. The power is switched ON again, the temperature will fall
below the setpoint and rise up to the setpoint. At that point autotuning is
completed, the PID constants are calculated and stored in memory until
the next autotuning or manual changes are made. For best results the
autotuning setpoint should be as close as possible to the control setpoint.
However, since the temperature will overshoot the autotuning setpoint
during the autotune by the full proportional band, Systems that cannot
tolerate that temperature should have autotuning setpoint one propor-
tional band value below the control setpoint.

35

Function [77] initiates unit autotuning.
On entering function [77] the function display reads 61.
The zone display shows the zone set for autotuning.
The upper display shows current temperature. When the top display
and function display are flashing the power is turned on.
When temperature reaches the Autotune setpoint the power goes off
and the function display shows 62. On completion of the autotuning the
controller returns to “RUN” Mode.

To stop the autotune press two buttons            and

 together

36

INPUTS

(BACK-
PLATE)

3 0. 2 6

+  -

MILLIVOLTMETER

30mV±2mV

COPPER WIRE

6.11   Function [78]

Calibration

Calibration is performed by inputting DC MV from a low Impedance
source (10 Ohm) and entering the precise value of the MV into the display.

UNIT WIRING:
Using copper wire, connect the positive and negative terminals of the
Input Connector to a precision millivolt meter and a low output
impedance source (10 ohm or less) set to 30mV ±2mV input.
Parallel-connect all thermocouple terminals of the Input Connector as
shown:

NOTE: To avoid any interference during calibration, disconnect
the RS-232 wires from the controller.