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2.8.1
Auto-Tuning Operation Steps
1.
The system is set up to run under real-world conditions.
2.
“PB and “TI” settings should not be set to zero.
3.
The LOCK parameter should be set to NONE.
4.
Set the set point to a normal operating value, or a lower value if overshooting beyond the
normal process value will cause damage.
5.
Press and hold the key until
appears on the upper display. Continue to hold the
“ ” key for an additional 3 seconds, else the display will revert to a “User Menu”
parameter.
6.
Press and hold the key until the TUNE indicator begins to flash.
7.
The Auto-Tuning process has begun.
NOTE:
During Auto-Tuning, the output will stay on until the Process Value reaches the setpoint. This is likely to
cause the temperature to exceed the setpoint.
Then, the output will remain off until the process value falls below the setpoint.
This will occur at least two times while the controller “learns” how to control your process.
Procedures:
Auto-Tuning can be applied either as the process is warming up (Cold Start) or as the
process has been in steady state (Warm Start). After the Auto-Tuning process is completed, the TUNE
indicator will stop flashing and the unit will revert to PID control by using its new PID values. The PID values
obtained are stored in nonvolatile memory.
2.8.2
Auto-Tuning Error
If Auto-Tuning fails, an ATER
message will appear on the upper display in any of the following
cases.
v
If PB exceeds 9000 (9000 PU, 900.0°F or 500.0°C)
v
If TI exceeds 1000 seconds
v
If the set point is changed during the Auto-Tuning process
2.8.3
Solution for an Auto-Tuning Error
1.
Try Auto-Tuning once again.
2.
Avoid changing the set point value during the Auto-Tuning process.
3.
Ensure PB and TI are not set to zero.
4.
Use manual tuning.
5.
Touch RESET
key to reset the
message.
