EVCO EPH4EXP Hardware manual - Manual (Page 26)

EVCO S.p.A. c-pro 3 | Hardware manual ver. 3.2 | Codice 114CP3E324
page 26 of 116
8 not connected
The maximum length of the connecting cables of the RS-485 port is 1,000 m (3,280 ft); also look at the Modbus specifications
and implementation guides manual (the document is available on the internet site www.modbus.org).
Connect the RS-485 port using a twisted pair.
The following table shows the function codes supported by the controller.
Function
code
Meaning
FC 01 read coils
FC 02 read discrete inputs
FC 03 read multiple registers
FC 04 read input registers
FC 05 write single coil
FC 06 write single register
FC 08 diagnostic
FC 15 write multiple coils
FC 16 write multiple registers
FC 23 read write multiple registers
For the settings about the RS-485 port look at chapter 6 “CONFIGURATION”.
MODBUS2
RS-485 port with Modbus master / slave communication protocol (configurable via application software).
The following drawing shows the aspect of the RS-485 port.
The following table shows the meaning of the pins of the RS-485 port.
Pin Meaning
1 common
2 not connected