Instruction Manual
N2020 Controller 
NOVUS AUTOMATION  4/7 
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. 
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 







