The N322T is a 2-output digital electronic controller for heating and cooling applications. It is available
with NTC thermistor input sensor, Pt100, Pt1000 or J/K/T type thermocouple. Sensor offset correction
is provided. The 2 independent outputs can be used as control or alarm.
Displays the
Compressor Protection Function by Supply Voltage Monitoring
, important in the
protection of compressors for refrigeration systems.
SPECIFICATIONS
INPUT SENSOR:
The input sensor type can be chosen form the options below (specified when
placing the order):
NTC
Thermistor, 10 k
@ 25 °C; range: –50 to 120 °C (-58 to 248 °F);
Accuracy: 0.6 °C (1.1 °F), with original sensor;
Sensor interchangeability: 0.75 °C (1.35 °F). This error can be compensated by the
offset
parameter in the controller.
Pt100 (
= 0.00385); Range: –50 to 300 °C (-58 to 572 °F);
Accuracy: 0.7 °C (1.3 °F); IEC-751.
Pt1000 (
= 0.00385);
Range: –200 to 530 °C (-328 to 986 °F);
Accuracy: 0.7 °C (1.3° F);
J, K or T thermocouple
(IEC-584)
:
Type J
: Range: 0 to 600 ºC (32 to 1112 ºF); Accuracy: 3 ºC (5.4 ºF);
Type K
: Range: -50 to 1000 ºC (-58 to 1832 ºF); Accuracy: 3 ºC (5.4 ºF);
Type T
: Range: -50 to 400 ºC (-58 to 752 ºF); Accuracy: 3 ºC (5.4 ºF);
Note
: In the controller with NTC input, a 3 m-sensor cable is bundled with the instrument. The
cable can be extended up to 200 m.
WARM-UP:
.......................................................................................................................... 15 minutes
MEASUREMENT RESOLUTION:
From –19.9 to 199.9 º with NTC, Pt100 and Pt1000: ........................................................................... 0.1
Elsewhere: ....................................................................................................................................... 1
OUTPUT1:
......................................... Relay SPDT; 1 HP 250 Vac / 1/3 HP 125 Vac (16 A Resistive)
................................................................................................... Optionally: Pulse, 5 Vdc, 25 mA max.
OUTPUT2:
.......................................................................................... Relay: 3 A / 250 Vac, SPST-NA
POWER SUPPLY:
........................................ 100~240 Vac/dc (± 10 %) or 24 Vdc/ac (12~30 Vdc/ac)
...................................................................... Mains frequency: 50~60 Hz. Power consumption: 5 VA
Caution
: check the power supply specification before energizing the controller.
DIMENSIONS
: .................................................................... Width x Height x Depth: 75 x 33 x 75 mm
............................................................................................ Panel cut-out: 70 x 29 mm; Weight: 100 g
ENVIRONMENT:
.................................................... Operating temperature: 0 to 40 °C (32 to 122 °F)
.................................................................................. Storage temperature: -20 to 60 °C -4 to 140 °F)
.....................................................................................Relative humidity: 20 to 85 % non-condensing
CASE:
..........................................Polycarbonate UL94 V-2; Protection: Front panel: IP65, Box: IP42
.............................................................................................................. Suitable wiring: Up to 4.0 mm²
RS-485 digital communication; RTU MODBUS protocol (optional)
Serial interface not isolated from input circuitry.
Serial interface isolated from input circuitry, except in 24 V powered model.
ELECTRICAL WIRING
Fig. 1
below shows the controller connections to sensor, mains and outputs.
Fig. 1
- N322T terminals
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:
Level
Function
0
Temperature measurement
1
Setpoint adjustment / Voltage indication
2
Configuration
3
Calibration
Upon power-up, the N322T 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 “
SP
” message shows up. To go back to level 0,
press
once more.
To access level 2 of parameters, press
for 2 seconds until the “
uNT
” message is shown.
Release the
key to remain in this level. Each new pressing on the
key will advance to the
next parameter in the 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.
2
If 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 (
SP1
and
SP2
) parameters are available, alternating the names with
their respective values. Adjust the desired temperature for each setpoint clicking on the
and
keys.
U
Voltage
- The screen voltage measurement. For values lower than 150 Vac and
higher than 254 Vac presents the message
0
.
Function available for model N322T-NTC-LVD.
SP
Set Point
- Temperature adjustment for control.
SP
value is limited to the values
programmed in
SPL
and
SPk
in the programming level.
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.
Unt
Temperature
Unit
- Selects display indication for degrees Celsius or Fahrenheit.
0
- Temperature in degrees Celsius
1
- Temperature in degrees Fahrenheit
typ
Input Type
- Selects the input sensor type to be connected to the controller.
Available only for thermocouple models, allowing selection of types J, K and T.
0
- Thermocouple type
J
1
- Thermocouple type
K
2
- Thermocouple type
T
ofs
Sensor Offset
- Offset value to be added to the measured temperature to
compensate sensor error.
spl
SP Low Limit
- Lower range for
SP1
and
SP2
.
SPL
must be programmed
with a lower value than
spK
.
spK
SP High Limit
- Upper range for
SP1
and
SP2
.
SPx
must be greater than
spl
.
kys
OUTPUT Hysteresis
: defines the differential range between the temperature
value at which the OUTPUT is turned on and the value at which it is turned off.
In degrees.
ale
Alarm Enable
:
0
Alarm disabled;
1
Buzzer alarm and output 2 pulsed (1 second);
2
Buzzer alarm and output 2 pulsed;
3
Output 2 pulsed (1 second);
4
Output 2 pulsed.
Function available for models N322T-NTC and N322TB-NTC.
For N322T-NTC model
1
and
2
parameter work as
3
and
4
parameters
respectively.
Alarm function works only for
fot
=
2
parameter.
Alt
Alarm Time
- Sets the time for which the alarm will be triggered.
1
to
255
seconds
To turn the alarm off before the programmed time, just press
for 1 second.
Function available for models N322T-NTC and N322TB-NTC.
Alarm function works only for
fot
=
2
parameter.
Act
Control action for OUTPUT 1:
0
Reverse: For heating applications. Outputs turn on when temperature is
lower than SP.
1
Direct: For cooling applications. Output turns on when temperature is
above SP.
(nt
Control
- Associates Setpoints and Outputs.
0
Setpoint is assigned to OUTPUT1 and Setpoint to OUTPUT2 (factory
setting).
1
Setpoint is assigned to OUTPUT2 where as Setpoint is directed to
OUTPUT1.
oft
Off time
- Defines the minimum
off
time for control OUTPUT. Once OUTPUT is
turned off, it remains so for at least the time programmed in
oft
. For
thermocouple inputs this parameter is not available. This parameter is intended
for refrigeration systems where longer compressor life is desired. For heating
systems, program
oft
to zero. Value in seconds, 0 to 999 s.
Ont
On time
- Defines the minimum
on
time for control OUTPUT. Once turned on,
OUTPUT 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
ont
to zero. Value in seconds, 0 to 999 s.
dly
Delay
- Delay time to start control. Upon power-on, control OUTPUT 1 is kept
off
until the time programmed in
dly
is elapsed. Its usage is intended to
prevent multiple compressors to start simultaneously after the turn-on of a
system with several controllers. Value in seconds, 0 to 250 s.
