NOVUS PRODUTOS ELETRÔNICOS LTDA www.novus.com.br 1/2
RUA ÁLVARO CHAVES, 155
PORTO ALEGRE – RS – BRASIL
90220-040
PHONE: (51) 3323 3600
FAX: (51) 3323 3644
INSTRUCTION MANUAL
INTRODUCTION
The Universal Analogical Input Modbus Module -
DigiRail-2A is a remote measuring unit with two
configurable analogical inputs. An RS485 serial
interface allows reading and configuration of these
inputs, through communication network. It's appropriate
for mounting on DIN 35 mm rails.
The inputs are electrically insulated from the serial
interface and the module supply. There is no electrical
insulation between inputs. There is also no electrical
insulation between serial interface and supply.
Configuration of the DigiRail-2A is performed through
the RS485 interface by using Modbus RTU commands.
The DigiConfig software allows the configuration of all
features of the DigiRail as well as its diagnostics. The
DigiConfig offers features for detecting the devices
present in the Modbus network and for configuring the
communication parameters of the DigiRail-2A.
This manual provides the instructions for installation
and connection of the module. The installer for
DigiConfig and the documentation regarding Modbus
communication for the DigiRail-2A (Communication
Manual of the DigiRail-2A) are included in the CD-ROM
which accompanies the product. They are also
available for download at www.novus.com.br.
SPECIFICATIONS
Inputs: 2 universal analogical inputs.
Input signals: Configurable. Refer to Table 1.
Thermocouples: Types J, K, T, R, S, B, N and E,
according to NBR 12771. Impedance >> 1MΩ
Pt100: 3 wires type, α= .00385, NBR 13773, Excitation
of 700µA. For using Pt100 2 wires, interconnect
terminals 2 and 3.
When gauging the module using the
calibrator for Pt100, be sure that the
minimum current required for it is
compatible with the specified excitation
current: 700µA.
Other Signals:
• 0 to 20 mV, -10 to 20 mV, 0 to 50 mV.
Impedance >> 1 MΩ
• 0 to 5 Vdc, 0 to 10 Vdc. Impedance >> 1 MΩ
• 0 to 20 mA, 4 to 20 mA.
Impedance = 100 Ω(+ 1.7 Vdc)
Overall accuracy (at 25°C): Thermocouples:
0.25% of the maximum range, ±1°C; Pt100, voltage
and current: 0.15% of the maximum range;
The 0-5 Vdc and 0-10 Vdc inputs in the
Standard model are not factory calibrated
and provide an accuracy of about 5%.
When gauged properly, they can provide an
accuracy of up to 0.15%.
Input Signal Maximum Measuring Range
Thermocouple J -130 to 940 °C (-202 to 1724 ºF)
Thermocouple K -200 to 1370 °C (-328 to 2498 ºF)
Thermocouple T -200 to 400 °C (-328 to 752 ºF)
Thermocouple E -100 to 720 °C (-148 to 1328 ºF)
Thermocouple N -200 to 1,300 °C (-328 to 2372 ºF)
Thermocouple R 0 to 1760 °C (-32 to 3200 ºF)
Thermocouple S 0 to 1760 °C (-32 to 3200 ºF)
Thermocouple B 500 to 1800 °C (932 to 3272 ºF)
Pt100 -200 to 650°C (-328 to 1202 ºF)
0 to 20 mV
-10 to 20 mV
0 to 50 mV
*0 to 5 Vdc Adjustable between -31000 and +31000
*0 to 10 Vdc
0 to 20 mA
4 to 20 mA
Table 1 – Sensors and signals accepted by the module
Sampling rate: from 2.5 to 10 samples per second
Internal compensation of cold junction for
thermocouples
Feed: 10 to 35 Vdc / 50 mA maximum. Internal
protection against polarity inversion.
Electrical insulation between inputs and
supply/serial port: 1000 Vac
Serial communication: RS485 at two wires, Modbus
RTU protocol. Configurable parameters: Communication
speed: from 1200 to 115200 bps; Parity: even, odd or
none
Key for restoring communication parameters: The
RCom key, at the front panel, will set the device in
diagnostics mode (address 246, baud rate 1200, parity
even, 1 stop bit), able to be detected and configured by
the DigiConfig software.
Frontal light indicators for communication and
status:
TX: Signalizes that the device is sending data
on the RS485 line;
RX: Signalizes that the device is receiving
data on the RS485 line;
Status: When the light is permanently on, this
means that the device is in normal operation; when
the light is flashing in a second interval
(approximately), this means that the device is in
diagnostics mode; when the light is flashing fast,
this means that there is an internal error.
Electromagnetic compatibility: EN 61326:2000
Operating temperature: 0 to 70 °C
Operational relative humidity: 0 to 90% RH
Envelope of the terminals: Polyamide
Assembly: DIN 35 mm rail
Dimensions: Refer to figure 1.
