TEMPERATURE CONTROLLER
N321R
OPERATING MANUAL V1.8x F
The N321R is a controller for cooling applications, with defrost function (forced compressor
shut-down). It accepts NTC, Pt100 and Pt1000 temperature probes, depending on the
product code (the user must observe the measurement range of the selected sensor). The
N321R control output is capable of driving a compressor load of up to 1 HP directly.
The features of a particular model (input sensor type, sensor range, mains supply, etc) are
identified by the label placed on the thermometer body.
SPECIFICATIONS
SENSOR INPUT:The sensor is chosen by the user at the time of purchase and is presented
on the upper side of the equipment box. The options are:
•Thermistor NTC, 10 k
@ 25 °C; Range: -50 to 120 °C (-58 to 248 °F);
Accuracy: 0.6 °C (1.1 °F);
Maximum error in the interchangeability of original NTC sensors: 0.75 °C (1.35 °F). This
error can be eliminated through the offset parameter of the equipment.
Note: For the NTC thermistor option, the sensor comes with the equipment. Its
operating range is limited to -30 to +105 °C (-222 to +221 °F). It has cable of 3 meters
in length, 2 x 0.5 mm², and can be extended up to 200 meters.
•Pt100; Range: -50 to 300 °C (-58 to 572 °F);
= 0,00385; 3 wires;
Accuracy: 0.7 °C (1.3 °F); according to IEC-751 standards;
•Pt1000; Range: –200 to 530 °C (-328 to 986 ºF);
= 0,00385; 3 wires;
Accuracy: 0.7 °C (1.3 °F).
Measurement Resolution:............................................................... 0.1 º from -19.9 to 199.9 º
..................................................................................... 1 ºC elsewhere
Note: The equipment keeps its precision all over the range, despite the lack of display
resolution in a part of the range does not allow its visualization.
OUTPUT1:...............................Relay SPDT; 1 HP 250 Vac / 1/3 HP 125 Vac (16 A Resistive)
POWER SUPPLY: .........................................100 to 240 Vac/dc (±10 %)
Optionally:................................................ 12 to 30 Vdc
Mains frequency: ..........................................50~60 Hz
Power consumption: .............................................5 VA
Dimensions: Width x Height x Depth: ............................................75 x 33 x 75 mm
Weight: .......................................................................................100 g
Panel cut-out: ....................................................................70 x 29 mm
Environment: Operating temperature:........................0 to 40 °C (32 to 104 ºF)
Storage temperature: ........................ -20 to 60 °C (-4 to 140 ºF)
Relative humidity:.................................................20 to 85 % RH
Case Polycarbonate UL94 V-2
Protection: Box IP42, Frontal panel IP65
Suitable wiring: Up to 4.0 mm²
Serial interface not isolated from input circuitry.
Serial interface isolated from input circuitry, except in 24 V powered model.
ELECTRICAL WIRING
Fig. 01 below shows the controller connections to sensor, mains and outputs.
Fig. 01 - N321R terminals
* The serial communication interface is optional.
Pt100 with 3 conductors: Terminals 11, 12 and 13 must have the same wire resistance for
proper cable length compensation. For 2 wire Pt100, short circuit terminals 11 and 13.
Recommendations for the Installation
•Temperature sensor drivers must go through the plant separate system for drivers of
control output and power supply if possible electroducts terrified.
•The controller's power should come preferably a campus network for instrumentation or
different from that used by phase control output.
•Installing RC filters (47 R and 100 nF, series combination) is strongly recommended at
contactor coils or any other inductors.
OPERATION
The controller requires the internal parameters to be configured according to the intended
use for the instrument.
The parameters are organized in 4 groups or levels.
0 Temperature Measurement
1 Setpoint Adjustment / Voltage indication
3 Calibration
Upon power-up, the controller display shows for 1 second its firmware version. This
information is useful when consulting the factory. Then, the temperature measured by the
sensor is shown on the display. This is the parameter level 0 (temperature measurement
level).
To access level 1, press for 1 second until the “
” message shows up. Pressing
again to go back to level 0.
To access level 2of parameters, press for 2 seconds until the “
” message is shown.
Release the key to remain in this level. Each new pressing on the key will advance
to the next parameter in that level. At the end of the level, the controller returns to the first
level (0).
Use the and keys to alter a parameter value.
Notes: 1 A parameter configuration is saved when the key is pressed to
advance to the next parameter in the cycle. The configuration is stored in a
non-volatile memory, retaining its value when the controller is de-energized.
2If no keyboard activity is detected for over 20 seconds, the controller saves
the current parameter value and returns to the measurement level.
Level 1 – Setpoint Adjustment
In this level only the Setpoint (SP) parameters are available, alternating the names with their
respective values. Adjust the desired temperature for each setpoint clicking on the and
keys.
The screen voltage measurement. For values lower than 150 Vac and
higher than 254 Vac presents the message 0.
Function available only for model N321R-NTC-LVD.
Temperature adjustment for control OUTPUT 1. SP value is limited to the
in the programming level (Parameter
Configuration, Level 2).
Level 2 – Configuration – Parameters Configuration Level
Contains the configuration parameters to be defined by the user, according to the system’s
requirements. Use and keys to set the value. The display alternates the parameter
name and respective value.
Selects display indication for degrees Celsius or
Temperature in degrees Celsius. (factory default)
Temperature in degrees Fahrenheit.
Sensor Offset - Offset value to be added to the measured temperature to
SP Low Limit - Lower range for SP. SPL must be programmed with a
SP High Limit - Upper range for
OUTPUT 1 Hysteresis: Defines the differential range between the OUTPUT
1 temperature value at which it is turned off. In degrees.
Off time - Defines the minimum off
time for control OUTPUT 1. Once
OUTPUT 1 is turned off, it remains so for at least the time programmed in
oft. This parameter is intended for refrigeration systems where longer
compressor life is desired. Value in seconds, 0 to 999 s.
On time - Defines the minimum on
time for control OUTPUT 1. Once turned
on, OUTPUT 1 remains so for at least the time programmed in
ont. For
thermocouple inputs this parameter is not available. This parameter is
intended for refrigeration systems where increased compressor life is desired.
For heating systems, program
to zero. Value in seconds, 0 to 999 s.
Delay time to start control. Upon power-on, control OUTPUT 1 is kept off
until the time programmed in
is elapsed.
Its usage is intended to prevent multiple compress
simultaneously after the turn-on of a system with several controllers.
Value in seconds, 0 to 250 s.
Defrost
Interval Base
Time base for
Defrost Time
Base
Time base for
Interval between defrost cycles. Can be selected 0 to 999 seconds/
minutes/hours, according the value specified at
Defrost duration. Can be 1 to 999 seconds / minutes / hours, according the
Hold the temperature indication throughout the defrost interval or the time
defined by this parameter.
Do not hold the indication during the defrost;
Time (seconds / minutes / hours)
the indication will remain held.
