7
DIRIS A17
- Ref.: 541 984 A
DIRIS A17
6. Communication MODBUS
®
6.1. General Information
The MODBUS
®
communication bus is available on
DIRIS A17
Z]^#!@!^Z]^#!@!`&
It is achieved via an RS485 serial link (2 or 3 wires) for using products from a PC or an API.
Y 4zJZ] ' `^X>
a distance of 1200 meters.
DIRIS 109 F X
DIRIS 110 F X
Programmable PLC
Programmable PLC
Other systems
Other systems
Repeater
0 -> NC
0 -> NC
6.2. Recommendations
It is necessary to use a shielded twisted pair (LIYCY type). In a disturbed environnement or large network (in terms
of length) we recommend the use of a shielded twisted pair (type LIYCY-CY).
A repeater should be used if the distance of 1200 m and/or maximum number of 32 products are exceeded.
@^! ? '
6.3. Communication structure
The MODBUS
®
used by the product involves a dialogue using a master-slave structure. The mode of communication
is the RTU (Remote Terminal Unit) using hexadecimal characters of at least 8 bits.
Structure of the MODBUS
®
sequence (question master -> slave):
Slave address
Function code
Address
Number of words to be
read
CRC 16
1 byte
1 byte
2 bytes
2 bytes
2 bytes
