Operating instructions

ııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııııı
www.fptgroup.com
Neo
Installation & Operating Instructions
Page 39
9.0 Serial Communications
9.1 RS-485 Communications
The Fenner QD:Neo has an RJ45 connector on the front of the control panel. This connector allows the user to set up a drive
network via a wired connection. The connector contains two independent RS485 connections, one for Fenner QD Protocol and
one for Modbus RTU. Both connections can be used simultaneously.
The electrical signal arrangement of the RJ45 connector is shown as follows:
The QBus data link uses the same communication protocol as is used for IrDA communication. This is used for the Master /
Slave function (refer to the Advanced User Guide for further information). Up to 62 slaves can be connected to one master
drive.
The Modbus interface allows connection to a Modbus RTU network as described below.
9.2 Modbus RTU Communications
9.21. Modbus Telegram Structure
The Fenner QD:Neo supports Master / Slave Modbus RTU communications, using the 03 Read Holding Registers and 06
Write Single Holding Register commands. Many Master devices treat the first Register address as Register 0; therefore it
may be necessary to convert the Register Numbers detail in section 0 by subtracting 1 to obtain the correct Register address.
The telegram structure is as follows:-
Command 03 - Read Holding Registers
Master Telegram Length Slave Response Length
Slave Address 1 Byte Slave Address 1 Byte
Function Code (03) 1 Byte Starting Address 1 Byte
1st Register Address 2 Bytes 1st Register Value 2 Bytes
No. of Registers 2 Bytes 2nd Register Value 2 Bytes
CRC Checksum 2 Bytes Etc...
CRC Checksum 2 Bytes
Command 06 - Write Single Holding Register
Master Telegram Length Master Telegram Length
Slave Address 1 Byte Slave Address 1 Byte
Function Code (06) 1 Byte Function Code (06) 1 Byte
Register Address 2 Bytes Regsieter Address 2 Bytes
Value 2 Bytes Register Value 2 Bytes
CRC Checksum 2 Bytes CRC Checksum 2 Bytes
1 CAN-
2 CAN+
3 0 Volt
4 QBus / Remote Keypad / PC Connection -
5 QBus / Remote Keypad / PC Connection +
6 +24 Vol Remote Keypad Power Supply
7 RS 485- Modbus RTU
8 RS 485+ Modbus RTU