Conair Thermolator TW-1 User Manual page 51

5
Set the setpoint to desired value.
6
Press and
Run
simultaneously to begin the Auto Tune. The pump ener-
gizes, the Actual display flashes "At" and the current
process temperature to indicate that an Auto Tune is
underway.
If Auto Tune is successful, the controller automatically
starts controlling using the new PID parameters.
If you press the STOP button or a fault occurs during the
Auto Tune, the control enters stop mode and Auto Tuning
immediately terminates. The Actual display stops flashing
"At." If a fault occurred, the control displays the appropri-
ate error message.
ERROR MESSAGE
A t d E v
A t t I
A t b a d
UGH025-0504
(the Setpoint Select button)
ERROR DESCRIPTION
Insufficient setpoint/process deviation.
If the absolute value of (setpoint - process value) is less than
25°F. The Auto Tune cannot be started until the temperature
difference is at least 25°F.
Auto Tune timed out. Auto Tune will time out if a stable
process value cannot be obtained 5 minutes into the tune, or if
the tuning process takes longer than 30 minutes. If this error
occurs, verify that you followed every requirement under "To
ensure a successful Auto Tune" and perform a second tune.
Invalid PID constants were generated.
The most likely causes of this error is a tune started inappro-
priately or an external element (i.e., loose thermocouple) that
upset the process while tuning was in progress. Verify that you
followed every requirement under "To ensure a successful
Auto Tune" and perform a second tune.
Thermolator TW Series
TW-1, TW-2
C
ONTROL
P
ERFORMING AN
A T
UTO UNE
O
PERATION
4-15