CD Automation REVO RT, User Manual

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28
REVO RT
from 35A to 90A
User’s manual
Automatic tune
Automatic tuning procedure allows a precise regulation without detailed knowledge of PID regulation
algorithm.
There are different types of tuning depending on your needs:
• Pre Tunn
• Self Tunn
• Tuning Once
9.1 Pre Tune
With the Pre Tune function, the instrument generates an oscillation
in order to be able to calculate the inertia and response of the
system. Based on the data collected, the instrument calculates
the optimal PID parameters for stable regulation.
NOTE: For better precision in the calculation of the PID
parameters, it is advisable to start the manual tuning procedure
when the process deviates by at least 10% from the full scale.
The Pre Tune function is enabled for each Loop, with the "Tune"
parameter, or via serial line by setting "2" on the parameters:
• P85 Add 2085 for Loop 1,
• P111 Add 2111 for Loop 2,
• P137 Add 2137 for Loop 3,
If the function is enabled, the Pre Tune button in the Test section
of the configurator will also be enabled.
To execute the Pre Tune function, press the key
PT
Pre Tune
o by serial write the value “1” on parameters with modbus
address:
• 1216 (for Loop1)
• 1217 (for Loop2)
• 1218 (for Loop3)
Once the function is completed, the parameter will be
reset to 0 automatically.
On the configurator, during the Pre Tune operation, the “AT”
LED on the configurator will be on.
Once the function to stop the tuning has been activated,
manually write “0” on the modbus word of the respective
command words
9
Set Point
PV PV
Start Tuning
Tempo Tempo
Set Point
Soglia Auto Tuning
PID Calculation
Enable EN
EN H C HB SC AT Man
PT
L1
Pre Tune
Enable
EN
EN H C HB SC AT Man
PT
L1
Pre Tune
The starting threshold of the tuning calculation is given by the formula
Tune treshold = Set Point - “Set Deviation Tune (P86 Add 2086)”
Example: If set point is 100.0°C and parameter P86 is 20.0°C the starting threshold for calculating the PID
parameters is (100.0 - 20.0) = 80.0°C.