Remberg ISO-plus-CAN, Руководство пользователя

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12 - User manual
7.3 Automatic tuning
Select 1 on parameter 31 (
Tune
word 2031).
Automatic tuning is always active and analyses constantly the difference setpoint-
process. If this difference is greater than the value selected on parameter 47
m.G.tu.
(Max Gap Tune - word 2047), the ISO-plus decides autonomously when to modify
PID parameters.
7.4 Manual tuning
Select 2 on parameter 31 (
Tune
word 2031).
The manual procedure allows the user a greater flexibility on deciding when to
update PID algorithm parameters.
This procedure is activated writing 1 on the word modbus 1205. The reference
threshold to calculate the new PID parameters is given by the result of the following
operation:
Tune threshold = Setpoint (word 1201) – Par. 32
s.d.tu.
(word 2032)
Ex.: if setpoint is 100.0°C and Par. 32
s.d.tu.
is 20.0°C, the threshold to calculate PID
parameters is (100.0–20.0) = 80.0°C.
N.B.: for greater accuracy in the calculation of PID parameters it is recommended to
launch the manual tuning when the process is far from setpoint.
7.5 AutoTuning Launch “Once”
Set 3 on parameter 31
tune
(word 2031). Autotuning procedure is executed only
once at next ISO-plus restart. If the procedure doesn’t work, will be executed at next
restart.
7.6 Synchronized tuning
Select 4 on parameter 31 (
Tune
word 2031).
This procedure has been conceived to calculate correct PID values on multi-zone
systems, where each temperature is influenced by the adjacent zones.
Writing on word 1205, the device works as follows:
Word 1004 value Action
0 Tune off.
1 Command output OFF
2 Command output ON
3 Tune active
4 Tune completed: command output OFF (read only)
5 Tune not available: softstart function enabled (only reading)
The operation of this Tuning mode is the following: the master switches-off or
turns-on all zones (value 1 or 2 on word 1205) for a time long enough to create
inertia on the system.
At this point the autotuning is launched (value 3 on word 1205). The controller
calculates the new PID values. When the procedure ends, it switches-off the control
output and sets the value 4 on word 1205. The master, which should always read the