NOVUS N321R User Manual

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Compressor

Protect

Enables compressor protection by voltage monitoring. If the network voltage
is not between the SetPoints (PL and (PK.

Disables compressor protection.

Enable compressor protection.

Function available only for model N321R-NTC-LVD.

(Pt

Compressor

Protect

Time

Determines a delay in the compressor shutting down when compressor

protection's activities by voltage monitoring. Adjustable time interval

between adjustable between 5 to 30 seconds.
Function available only for model N321R-NTC-LVD.

(PL

Low

Limit

Voltage lower limit used by the compressor protection. Voltage minimum

value that the compressor can operate.
Parameter adjustable between 150 to 254 Vac must be obligatorily 5 Vac
lower than the value set at the higher limit ((PH).
Function available only for model N321R-NTC-LVD.

(PH

High

Limit

Voltage lower limit used by the compressor protection. Voltage minimum

value that the compressor can operate.
Parameter adjustable between 150 to 254 Vac must be obligatorily 5 Vac
higher than the value set at the lower limit ((Pl).
Function available only for model N321R-NTC-LVD.

Add

Adress - Controllers with the optional RS485 Modbus RTU communication

interface have the Add parameter at the Configuration level. Set a unique

Modbus address for each equipment connected to the network. Address range
is from 1 to 247.

Level 3 – Calibration Level
The controller is factory calibrated. The following parameters should be accessed only by
experienced personnel. To enter this cycle, the

key must be kept pressed for 4 seconds.

Don’t press the

and

keys if you are not sure of the calibration procedures.

Just press the

key a few times until the temperature measurement level is

reached again.

pas

Password - Enter the correct password to unlock write operations for the
parameters in the following levels.

[Al

Calibration low - Offset value of the input. It adjusts the lower

measurement range of the sensor.

[Ak

Calibration High - Gain calibration. It adjusts the upper measurement
range of the sensor.

Uol

Voltage Calibration - Offset adjustment for calibrating the voltage

indication.
Function available only for model N321R-NTC-LVD.

[JL

Cold Junction Offset calibration - This parameter is available only for

thermocouple.

FA(

Factory Calibration - Restores factory calibration parameters. Change

from 0 to 1 to restore the calibration parameters with factory values.

Prt

Protection - Defines the levels of parameters that will be password

protected. See "Configuration Protection" for details.

Pa(

Password Change - Allows changing the current password to a new one.

Values from 1 to 999 are allowed.

Sn2

Serial number - First part of the controller electronic serial number.

sn1

Serial number - Second part of the controller electronic serial number.

sn0

Serial number - Third part of the controller electronic serial number.

WORKING WITH THE CONTROLLER

The controller turns on and off the compressor output such as to maintain the temperature at
the selected Setpoint. The front panel display shows the symbol

whenever the

compressor is active.
The defrost process of this controller is executed by stopping the compressor. This

procedure is done every time interval defined by the user. The control output remains off by
time also defined by the user. During the defrost procedure the temperature indication can

be held by adjusting the parameter dfk.
The df1 and dft parameters define, respectively, the time interval between defrosts and
the duration of the defrost cycle. The controller display shows the symbol to indicate that a
defrost cycle is in progress.

Manual defrost: The

key allows that a defrost cycle be initiated of terminated

immediately. Pressing this key for 1 second will toggle the current defrost status.

CONFIGURATION PROTECTION

A protection system to avoid unwanted changes to the controller parameters is implemented.
The level of protection can be selected from partial to full. The following parameters are part

of the protection system:

Pas

When this parameter is presented, the correct password must be entered to allow

changes of parameters in the following levels.

Prt

Defines the level of parameters that will be password protected:
1 - Only calibration level is protected (factory configuration);
2 - Calibration and Configuration levels are protected;
3 - All levels are protected - Calibration, Configuration and SP.

PA(

Parameter for definition of a new password. Since it is located in the calibration

level, can only be changed by a user that knows the current password. Valid
passwords are in the range 1 to 999.

Configuration protection usage
The PAS parameter is displayed before entering a protected level. If the correct password is

entered, parameters in all following levels can be changed. If wrong or no password is
entered, parameters in the following levels will be read only.

Important notes:
1 - After five consecutive attempts to enter a wrong password, new tentative will be blocked

for the next 10 minutes. If the current valid password is unknown, the master password
can be used only to define a new password for the controller.

2 - The password for a brand new device is 111.

MASTER PASSWORD

The master password allows user to define a new password for the controller, even if the current
password is unknown. The master password is based in the serial number of the controller, and

calculated as following:

[ 1 ] + [ higher digit of SN2 ] + [ higher digit of SN1 ] + [ higher digit of SN0 ]

for example the master password for the device with serial number 987123 465 is: 1936

As follows: 1 + sn2= 987; sn1= 123; sn0= 465 = 1 9 3 6

How to use the master password:
1 - Enter the master password value at PaS prompt.
2 - Go to PA( parameter and enter the new password, which must not be zero (0).
3 - Now you can use this new password to access all controller parameters with modify rights.

ERROR MESSAGES

Probe measurement errors force the controller outputs to be turned off. The cause for these

errors may have origin in a bad connection, sensor defect (cable or element) or system
temperature outside the sensor working range. The display signs related to measurement

errors are shown below.

Measured temperature exceeded maximum allowed range for the

sensor.

Broken Pt100 or Pt1000. Short circuited NTC sensor.

Measured temperature is below minimum measurement range of the

sensor.

Short circuited Pt100 or Pt1000. Broken NTC.

COMPRESSOR PROTECTION (N321R-NTC-LVD)

The controller constantly monitors the voltage of power network and shuts the compressor if
this tension is not within limits. These limits are defined in parameters (PL and (Pk,

adjustable between 150 and 254 Vac. In addition to turning the compressor off, the driver
passes the signal on your display this occurrence: Toggles the indication of voltage value

measured with the temperature value.
When the voltage exceeds limits (lower than 150 Vac and higher than 254 Vac) is signaling
to indicate temperature alternating with the message 0.

WARRANTY

Warranty conditions are available on our web site