14 - ATR224 - DRR224 - User manual
7.2
Automatic Tune
Automatic tuning procedure allows a precise regulation without delving into the PID regulation
algorithm. Selecting Auto on par. 73
tun.1
(for the regulation loop 1), the controller analyzes the proces
oscillations and optimizes the PID parameters.
Led
TUN
flashes.
If the PID parameters are not yet selected, at the device switch-on, it is automatically launched the
manual Tuning procedure described into the next paragraph.
7.3
Manual Tune
Manual procedure allows the user greater flexibility to decide when to update
PID algorithm parameters. During the manual tuning, the device generates a step to analyze the
system inertia to be regulated and, according to the collected data, modifies PID parameters.
After selecting
Manu.
on par. 73
tun.1
, the procedure can be activated as follows:
• Running Tuning by keyboard:
Press
FNC
until display 2 shows tunE with display 1 on dis. and then press
SET
: display 1 shows Enab.
Led
TUN
switches ON and the procedure starts.
• Running Tuning by digital input:
Select t
unE
on par. 231
d.i.1.F.
. At first activation of digital input (commutation on front panel) led
TUN
led switches on and at second activation switches off.
To avoid an overshoot, the treshold where the controller calculates new PID parameters is determined
by this operation:
Tune threshold = Setpoint -
“Set Deviation Tune”
(par. 74
s.d.t.1
)
Ex.: if the sepoint is 100.0∞C and the Par.32
s.d.t.1
is 20.0∞C the threshold to calculate PID parameters
is (100.0 - 20.0) = 80.0∞C.
For a greater precision on PID parameters calculation it is suggested to start the manual tuning
procedure when the process deviates from the setpoint.
7.4
Tuning once
Set
once
on parameter 73
tun.1
.
Autotuning procedure is executed only once at next device restart. If the procedure doesn’t work, will
be executed at next restart.
7.5
Digital input functions
The ATR224 and DRR224 functions related to digital inputs, can be enabled by parameter 231
d.i.1.F.
.
•
2t.Sw.
: Two threshold setpoint modification: with digital input active the device regulates on
SET
2,
otherwise reulates on
SET
1;
•
run.
: The regulation is enabled only with digital input active,
•
tune
: Enables/disables the Tuning if par. 73
tun.1
is selected as
manu.
;
•
au.ma.i.
: If par. 48
a.ma.1.
is selected as
enab.
or
en.sto.
, with impulse command on digital input, the
device switches the related regulation loop, from automatic to manual and vice versa.
•
au.ma.c.
: If par. 48
a.ma.1.
is selected as
enab.
or
en.sto.
the devices switches to manual the related
regulation loop, with digital input active, otherwise the regulation is automatic.
•
Act.ty.
: the device execute a cooling type regulation with digital input active, otherwise the
regulation is of heating type;
•
M.reS.
: Allows the reset of the output if manual reset is active for the alarms and for the command
outputs.