Elseta IOMOD 4RTD User Manual

IOMOD 4RTD User Manual Modbus
Introduction
IOMOD 4RTD is used for temperature data monitoring over Modbus or IEC-60870-103 using resistance temperature
detector (RTD) platinum sensors. Up to 4 RTD temperature sensors can be connected at once.
Features
● Temperature sense with ±0.5 °C accuracy over all operating conditions;
● Selectable PT100 ar PT1000 RTD temperature sensor for every channel (2, 3 or 4 wire);
● 2.5kV(rms) isolated RTD inputs;
● Configurable temperature and sensors' fault detection for every channel;
● Temperature sensing range from -200 up to 800 °C when using platinum RTD sensors;
● Configurable Modbus or IEC-60870-103 settings: Slave ID, baud rate, parity and stop bits, RS485 terminating
resistor, etc.
● Firmware upgrade over USB.
Operational Information
IOMOD uses Modbus (RTU) or IEC-60870-103 protocols over RS485 connection, which can be used for cable lengths up
to 1500 meters and connect up to 30 devices on one line. Default Modbus and IEC-60870-103 settings are: 9600
bauds/s baudrate, 8N1, Slave (Link) address - 1.
To read temperature using Modbus (RTU) protocol user can use device with default settings without configuring it. To
read temperature from RTD sensor, send 04 Modbus command (Read Input Registers) with resolution of two registers
from 0 to 7. Odd numbers represent least significant words, even numbers represent most significant words. For
example, to read temperature measured by first RTD, read register 0 and 1, where register 0 is least significant word.
Two words read by Modbus represent a float type (IEEE-754 compatible) variable.
For further information regarding setting temperature parameters and configurable options please refer to table shown
below, also supported MODBUS functions described in paragraphs described below.
CONFIGURABLE OPTIONS
Slave Address
Baudrate
Data, Stop and Parity bits
RS485 Terminating Resistor
RTD parameters
Default settings
Setting temperature limits
Fault configuration
Status LED
Status LED can be in 2 colors :
Blue - Device connected to USB.
Green - Normal operation.
Rx/Tx LED
The RX/TX LED on the IOMod flashes when data is either being transmitted or received via the RS485 port.
OVER USB
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
OVER MODBUS
No
No
No
No
No
No
Yes
Yes