Modbus Rtu Communications; Modbus Rtu Specification; Rj45 Connector Configuration; Modbus Telegram Structure - Invertek Drives Optidrive ODE-2-11005-1H01 Series User Manual

8. Modbus RTU Communications

8.1. Introduction
The Optidrive E2 can be connected to a Modbus RTU network via the RJ45 connector on the front of the drive.
8.2.

Modbus RTU Specification

Protocol
Error check
Baud rate
Data format
Physical signal
User interface
8.3.

RJ45 Connector Configuration

For full MODBUS RTU register map
information please refer to your Invertek
When using MODBUS control the Analog and
can be configured as shown in section 7.3
8.4.

Modbus Telegram Structure

The Optidrive ODE-2 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 8.5 by subtracting 1 to obtain the correct Register address. The telegram structure is as follows:-
Command 03 – Read Holding Registers
Master Telegram Length
Slave Address 1 Byte
Function Code (03) 1 Byte
1 st Register Address 2 Bytes
No. Of Registers 2 Bytes
CRC Checksum 2 Bytes
8.5.

Modbus Register Map

Register Par. Supported
Type
Number Commands
1 - R/W
2 - R/W
4 - R/W
6 - R
7 R
8 R
11 - R
20 P00-01 R
21 P00-02 R
22 P00-03 R
23 P00-08 R
24 P00-09 R
All user configurable parameters are accessible as Holding Registers, and can be Read from or Written to using the appropriate Modbus
command. The Register number for each parameter P-04 to P-047 is defined as 128 + Parameter number, e.g. for parameter P-15, the register
number is 128 + 15 = 143. Internal scaling is used on some parameters, for further details, please contact your Invertek Drives Sales Partner.
Optidrive ODE-2 User Guide Revision 3.20
Modbus RTU
CRC
9600bps, 19200bps, 38400bps, 57600bps, 115200bps (default)
1 start bit, 8 data bits, 1 stop bits, no parity.
RS 485 (2-wire)
RJ45
Drives Sales Partner.
Digital Inputs
Slave Response Length
Slave Address 1
Starting Address 1
1 st Register Value 2
2 nd Register Value 2
Etc...
CRC Checksum 2
Function
Low Byte
03,06 Drive Control Command
03,06 Modbus Speed reference setpoint
03,06 Acceleration and Deceleration Time
03 Error code Drive status
03 Output Motor Frequency
03 Output Motor Current
03 Digital input status
03 Analog Input 1 value
03 Analog Input 2 value
03 Speed Reference Value
03 DC bus voltage
03 Drive temperature
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Command 06 – Write Single Holding Register
Master Telegram
Byte Slave Address
Byte Function Code (06)
Bytes Register Address
Bytes Value
CRC Checksum
Bytes
Range Explanation
High Byte
0..3 16 Bit Word.
Bit 0 : Low = Stop, High = Run Enable
Bit 1 : Low = Decel Ramp 1 (P-04), High = Decel
Ramp 2 (P-24)
Bit 2 : Low = No Function, High = Fault Reset
Bit 3 : Low – No Function, High = Coast Stop
Request
0..5000 Setpoint frequency x10, e.g. 100 = 10.0Hz
0..60000 Ramp time in seconds x 100, e.g. 250 = 2.5 seconds
Low Byte = Drive Error Code, see section 10.1
High Byte = Drive Status as follows :-
0 : Drive Stopped
1: Drive Running
2: Drive Tripped
0..20000 Output frequency in Hz x10, e.g. 100 = 10.0Hz
0..480 Output Motor Current in Amps x10, e.g. 10 = 1.0 Amps
0..15 Indicates the status of the 4 digital inputs
Lowest Bit = 1 Input 1
0..1000 Analog input % of full scale x10, e.g. 1000 = 100%
0..1000 Analog input % of full scale x10, e.g. 1000 = 100%
0..1000 Displays the setpoint frequency x10, e.g. 100 = 10.0Hz
0..1000 DC Bus Voltage in Volts
0..100 Drive heatsink temperature in ºC
1 No Connection
2 No Connection
3 0 Volts
4 -RS485 (PC)
5 +RS485 (PC)
6 +24 Volt
7 -RS485 (Modbus RTU)
8 +RS485 (Modbus RTU)
Warning:
This is not an Ethernet
connection. Do not connect
directly to an Ethernet port.
Length Slave Response
1 Byte Slave Address
1 Byte Function Code (06)
2 Bytes Register Address
2 Bytes Register Value
2 Bytes CRC Checksum
Length
1 Byte
1 Byte
2 Bytes
2 Bytes
2 Bytes
25