Micromod Micro-DCI: 53SL6000 Single Loop Controller - Manual (Page 110)

Table 9-2. Easy-Tune Parameters
conF → EZ
Prompt Description Dft
cM Control Mode
Select the desired control action(s) for
the process:
P, PI, PID, PD
If previous Easy-Tune results indicated
the ratio of process dead time - Wp
(WP) to the process time lag - Tp (tP)
was greater than 0.5, then PID should
be selected for control mode. P
tLiM Limiting Settling Time
It is set to the time in seconds allowed
for the process to settle and the pre-
liminary step response to be detected. 0.0
dPV PV Excursion Limit
It is a percentage entered as a nu-
meric value that prevents excessive
changes in PV. 0.0
dout Output Step
It is set to the size of the output
change in percent that is used during
the tuning operation. This value can
be positive or negative, depending
on the direction of the output change
selected with the reverse parameter
(conF-cn.1-rSV). The value entered
should be large enough to cause
significant, but allowable PV changes
in the process. 0.0
dPPV Preliminary PV Step Disturbance
It is set to the change in PV required
to complete the preliminary step
operation. This value should be
approximately 1/4 th the expected
change caused by the setting of
dout. (This value is not 1/4 th of dout
because the expected PV change is
dependent upon process gain and
dout.) 2.0
PLiM Parameter Modify
Selecting on allows Easy-Tune to
modify the characterization values in
a conservative direction: that is,
overshoot is reduced compared to
control operation using the ITAE
calculated values. oFF
APLd Automatic Tuning Parameter Entry
The default, oFF, indicates the
calculated tuning values for
parameters conF-cn.1(cn.2)-Pb, tr,
and td will not be automatically
entered, but available for review in
conF-EZ-EPb, Etr, and Etd (see Section
9.8.2, Easy-Tune Determined Values).
Change to on for automatic entry. oFF
Table 9-2. Easy-Tune Parameters
conF → EZ
Prompt Description Dft
run? Run Select
During execution, the Easy-Tune LED
flashes and tunE appears in the green
dro. Upon successful completion, the
Easy-Tune LED stops flashing and the
green dro no longer displays the tunE
mnemonic. If an error or warning
condition occurs during execution,
the Easy-Tune LED changes to a
steady-state-on condition and a
mnemonic is displayed in the green
dro that identifies the error or warning.
Pressing the mode/select push button
clears the display. After taking the
appropriate corrective action(s), Easy-
Tune can be restarted by selecting
YeS at the run? prompt in the EZ menu. no
9.8.2 Easy-Tune Determined Values
The Easy-Tune calculated values can be viewed at
the prompts listed in Table 9-3. If conF-EZ-APLd
(in Table 9-2) was left at the default value (oFF),
then conF-EZ-EPb, Etr, and Etd values will not be
automatically written into the PID constants.
Table 9-3. Easy-Tune Determined Values
conF → EZ
Prompt Description Dft
KP Easy-Tune calculated gain. 0.0
tP Easy-Tune calculated first order time
constant. 0.0
WP Easy-Tune calculated dead-time. 0.0
EPb Resultant %PB value calculated by
Easy-Tune. 0.0
Etr Resultant reset time value calculated
by Easy-Tune. 0.0
Etd Resultant derivative time value
calculated by Easy-Tune. 0.0
9.8.3 Easy-Tune Status Responses
If Easy-Tune responds with an error or warning
condition during execution, the tune LED changes
from a flashing to a steady-state-on condition and a
mnemonic appears in the green dro that identifies
the error or warning.
The Easy-Tune responses are provided in the sec-
tions that follow. After taking the appropriate cor-
rective action(s) for the error or warninig condition,
Easy-Tune can be restarted by selecting YeS at the
run? prompt in the EZ menu.
Section 9. Commissioning 53SL6000 Instruction Manual
9-7