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Error Codes
If an error code cannot
be cleared by using
the actions provided,
contact factory.
Display
Problem
Actions
Open Sensor
Check sensor,
wiring, and Input.
Reversed Sensor
Check the type
selection in
the Input menu,
and check sensor
polarity.
Loop Break
Correct problem
and reset
controller.
Checksum Error
Press any key
RAM Error
to perform a
Defaults Loaded
soft reset and
EEPROM Write Failure
reinitialize
controller.
Power Fail Resume
No further resume
Feature Disabled
actions available.
Plus other
Unexpected or
Reset
2-Digit
Invalid Interrupt
controllers
Code
7)
While monitoring the recording device, decrease the
proportional band value by repeatedly halving the value
until a small, sustained temperature oscillation is
observed. Measure the period of one cycle of oscillation
(“T” on the diagram below).
8)
Divide the period of oscillation (T) by eight. The resulting
number is the correct Derivative
time in seconds.
Multiply this number by four. This is the correct Integral
time
in seconds.
9)
Multiply the bandwidth value obtained in Step 7 by 1.66
and enter this as the new proportional band value.
T
Manual Tuning
Manual Tuning Procedure
(Zeigler-Nichols PID Method)
This tuning method may be used for non-temperature control
processes or if the spread between ambient temperature and
process operating temperature is small. For best results, the
use of a recording device is required when tuning with this
method.
1)
For temperature control processes, disable any cooling
device used.
2)
With the power off and the controller NOT in the Key
Lockout security level, apply power and immediately put
the controller in Standby mode by pressing the Mode/
Enter
key for three seconds, the Raise
key until
appears and press the Mode/Enter key again.
3)
If you have a direct-acting output, it must be disabled
before proceeding further
=
.
4)
Under the Control menu, make sure that the derivative
term
, the offset term
, and the integral
term
are all set to zero, and the proportional
band
or
is set to the maximum setting.
5)
Adjust setpoint to the desired value with the Raise/Lower
keys.
6)
Press the Mode/Enter
key for four seconds, the Raise
key twice
, and the Mode/Enter key again to
return the controller to normal operation.
While some processes
other than heat or cool
applications may
respond successfully to
autotuning procedures,
the controller may need
to be manually tuned
for non-temperature
processes.
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