NOVUS N2020 Controller User Manual
Page 6
N2020 Controller
NOVUS AUTOMATION
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CONFIGURATION PROTECTION
The controller provides means for protecting the parameters
configurations, not allowing modifications to the parameters values,
avoiding tampering or improper manipulation. The parameter
Protection (PROt), in the Calibration level, determines the
protection strategy, limiting the access to particular levels, as shown
by the below.
Protection Level
Protection Levels
1
Only the Calibration level is protected.
2
Calibration and Input levels are protected.
3
Alarms, Input and Calibration levels are
protected.
4
Program, Alarms, Input and Calibration levels
are protected.
5
Tuning, Program, Alarms, Input and
Calibration levels are protected.
6
All levels are protected, but the SP screen in
the Operation level.
7
All levels are protected, including SP.
Table 03 – Levels of Protection for the Configuration
ACESS PASSWORD
The protected levels, when accessed, request the user to provide the
Access Password for granting permission to change the
configuration of the parameters on these levels. The prompt PASS
precedes the parameters on the protected levels. If no password is
entered, the parameters of the protected levels can only be
visualized.
The Access Password is defined by the user in the parameter
Password Change (PAS.(), present in the Calibration Level. The
factory default for the password code is 1111.
PROTECTION ACCESS PASSWORD
The controller foresees a safety system which helps to avoid the
input of many passwords, trying to insert the correct one. Once 5
consecutive invalid passwords are inserted, the controller stops to
accept passwords for 10 minutes.
MASTER PASSWORD
The Master Password is intended for allowing the user to define a
new password in the event of it being forgotten. The Master
Password doesn’t grant access to all parameters, only to the
Password Change parameter (PAS(). After defining the new
password, the protected parameters may be accessed (and
modified) using this new password.
The master password is made up by the last three digits of the serial
number of the controller added to the number 9000.
As an example, for the equipment with serial number 07154321, the
master password is 9 3 2 1.
Controller serial number is displayed by pressing
for 5 seconds.
DETERMINATION OF PID PARAMETERS
Automatic tuning allows the controller to obtain P.I.D parameters
(proportional band, full rate, derivative time).
During the process of determining automatically the PID parameters,
the system is controlled in ON/OFF in the programmed Setpoint. The
auto-tuning process may take several minutes to be completed,
depending on the system. The steps for executing the PID auto-
tuning are:
- Turn-off the outputs (RUN= NO).
- Adjust the SP value desired for the process.
- Enable auto-tuning at the parameter (ATUN= FAST or FULL)
- Turn-on the outputs (RUN= YES).
The option FAST performs the tuning in the minimum possible time,
while the option FULL gives priority to accuracy over the speed.
The sign TUNE remains lit during the whole tuning phase. The user
must wait for the tuning to be completed before using the controller.
During the automatic tuning execution, PV oscillations may be
induced in the process around the setpoint.
If the tuning does not result in a satisfactory control, refer to Table 04
for guidelines on how to correct the behavior of the process.
PARAMETER
VERIFIED PROBLEM
SOLUTION
Proportional Band
Slow answer
Decrease
Great oscillation
Increase
Rate Integration
Slow answer
Increase
Great oscillation
Decrease
Derivative Time
Slow answer or instability
Decrease
Great oscillation
Increase
Table 04 - Guidance for manual adjustment of the PID parameters
For further details on PID tuning, visit our web site:
MAINTENANCE
PROBLEMS WITH THE CONTROLLER
Connection errors and inadequate programming are the most
common errors found during the controller operation. A final revision
may avoid loss of time and damages.
The controller displays some messages to help the user identify
problems.
MESSAGE
DESCRIPTION OF THE PROBLEM
----
Open input. No sensor or signal.
Err1
Err6
Connection and/or configuration problems. Check
the wiring and the configuration.
Other errors messages showed by the controller represent internal
damages which implies necessarily in the submission of the
equipment for maintenance.
CALIBRATION OF THE INPUT
Visit our web site for further information
IDENTIFICATION
N2020 - PRR
Basic version. Three outputs.
OUT1= pulse / OUT2= relay / OUT3= relay
N2020 - PRRA
For outputs.
OUT1= pulse / OUT2= relay / OUT3= relay
OUT4= Analogic output 0-20 / 4-20 mA