N2020 Controller
NOVUS AUTOMATION
4/7
OUT indicator
: It shows the instantaneous state of the controller
output(s).
A1 and A2 indicator
: signalize the occurrence of alarm situation.
P key
: Key used to forward the successive parameters and
parameters cycles.
Increment key and
Decrement key
: allow altering the
values / conditions of the parameters.
Back key
: allow altering the values of the parameters.
START-UP
Upon the energizing, the controller shows the number of its software
version in the first 3 seconds. Then, it shows the process variable
value (
PV
) measured (temperature) on the upper display. The SP
value is showed on the lower display. This is the
Indication Screen
.
To operate in a process, the controller is required to be configured
previously. The configuration consists of a definition of each one of
the several parameters showed. The user must understand about the
importance of each parameter and, for each one, determine one valid
condition or a valid value.
The configuration parameters are together in affinity groups, known
as parameters cycles. The 6 levels of parameters are:
Operation / Tuning / Program / Alarms / Input / Calibration
The
P
key is used for accessing the parameters within a level:
Keeping the
P
key pressed, at every 2 seconds the controller jumps
to the next level of parameters, showing the first parameter of each
level:
PV
>
atvn
>
ptol
>
fva1
>
type
>
pass
>
PV
…
To enter a particular level, simply release the “
P”
key when the first
parameter in that level is displayed. To walk through the parameters
in a level, press the “
P”
key with short strokes. To go back to the
previous parameter in a cycle, press
.
Each parameter is displayed with its prompt in the upper display and
value/condition in the lower display. Depending on the level of
parameter protection adopted, the parameter
PASS
precedes the
first parameter in the level where the protection becomes active. See
section
CONFIGURATION PROTECTION
.
DESCRIPTION OF THE PARAMETERS
OPERATION CYCLE
PV + SP
PV indication
. The measured temperature value (PV)
is shown on the upper display (red). Control Setpoint
(SP) value is shown on the lower display (green).
(trl
Control Mode:
avto
- in automatic mode.
Man
- in manual mode.
PV + MV
MV Value
- The upper display shows PV value and
the lower display shows the
percentage
of MV
applied to the control output.
In automatic control mode, the MV value is showed
visually only. In manual control mode, the MV value
may be changed by the user. To differ this screen
from SP screen, the MV value blinks constantly.
E pr
Enable Program
Selects the ramp and soak profile
program to be executed.
no
- the program is not executed
yes
- the program is executed
With enabled outputs (
RvN
=
YES
), the program
starts right after the program is selected.
rvn
RUN Function
. Enables control outputs and alarms.
YES
- Outputs enables.
NO
- Outputs not enabled.
TUNING CYCLE
Atvn
Auto-Tune
: Enables the auto-tuning function for the
PID parameters (
pb
,
ir
,
dt
). Refer PID Parameters
Determination chapter in this manual and on website
www.novusautomation.com
for further details.
0ff
- Turned off. (no PID tuning)
Fast
- Execute the tuning in fast mode.
full
- Execute the tuning in accurate mode.
PB
Proportional Band
- Value of the term P of the
control mode PID, in percentage of the maximum span
of the input type. Adjust of between 0 and 500.0 %.
When set to zero (0), control action is ON/OFF.
ir
Integral Rate
- Value of the term
I
of the PID
algorithm, in repetitions per minute (Reset).
Adjustable between 0 and 99.99. Displayed only if
proportional band
≠
0.
dt
Derivative Time
- Value of the term
D
of the control
mode PID, in seconds. Adjustable between 0 and 300.0
seconds. Displayed only if proportional band
≠
0.
(t
Cycle Time
- Value in seconds in the PWM cycle
period of PID control. Adjustable between 0.5 and
100.0 seconds. Displayed only if proportional band
≠
0.
kyst
Control Hysteresis
- Is the hysteresis for ON/OFF
control (set in temperature units). This parameter is
only used when the controller is in ON/OFF mode
(
Pb
=
0
).
A(t
Action Control
:
re
Control with
Reverse Action
. Appropriate for
heating
. Turns control output on when PV is
below SP.
dir
Control with
Direct Action
. Appropriate for
cooling
. Turns control output on when PV
is above SP.
sfst
SoftStart Function
– Time interval, in seconds, in
which the control limits the speed of increase of the
control output (MV). From 0 to 9999 s.
Zero value ( 0 ) disables the SoftStart function.
Displayed only if proportional band ≠ 0.
0vt1
0vt2
0vt3
Assign functions to the output channels OUT1, OUT2
and OUT3:
Off
Not used.
(trl
Control output.
A1
Alarm 1 output.
A2
Alarm 2 output.
Lbd
Loop Break Detect Alarm.
0vt4
Operation mode of OUT4 output channel:
Off
Not used.
(trl
Digital control output (0 or 20 mA)
A1
Alarm output 1.(0 or 20 mA)
A2
Alarm output 2.(0 or 20 mA)
Lbd
Acts as the output for LB function
(.020
Analogical Control Output 0-20 mA
(.420
Analogical Control Output 4-20 mA
p.020
PV Retransmission 0-20 mA
p.420
PV Retransmission 4-20 mA
s.020
SP Retransmission 0-20 mA
s.420
PV Retransmission 4-20 mA