Leroy-Somer POWERDRIVE MD User Manual

137
COMMISSIONING MANUAL
POWERDRIVE MD
Variable speed drive
OPERATION WITH MODBUS RTU
LEROY-SOMER
3871 en - 2011.05 / h
6.4.3 - Parameter mapping
POWERDRIVE MD drives are configured using a
menu.parameter notation.
The "menu" and "parameter" indices can take the values 0 to
99. Menu.parameter is assigned to a MODBUS RTU register
menu x 100 + parameter.
In order to map the parameters correctly, the slave
increments (+1) the address of the received register.
Example: X = menu; Y = parameter
6.4.4 - Data encoding
MODBUS RTU uses a "big-endian" representation for the
addresses and data items (except for the CRC which is
"little-endian"). This means that, when a numerical quantity
"bigger" than one byte is transmitted, the most significant byte
is sent first.
For example:
6.4.5 - Function codes
The function code determines the context and format of the
message data.
• Function code 3: Read multiple
Reads a contiguous array of registers. The slave imposes an
upper limit on the number of registers which can be read. If
the limit is exceeded, the slave does not respond.
Note: 99 parameters maximum can be read.
Frame sent by the Master:
Frame returned by the slave:
Where n = 3 + number of bytes to be read.
Drive parameter
Register address
(protocol level)
X.Y (X x 100) + (Y – 1)
Examples:
01.02 101
01.00 99
00.01 0
12.33 1232
1
st
2
nd
…
16 – 0x1234 would be: 0x1 0x3
Function code
Description
Decimal Hexadecimal
3 0x03
Read multiple 16-bit registers or
words
6 0x06
Write single 16-bit register or
word
16 0x10
Write multiple 16-bit registers or
words
23 0x17
Read and write multiple 16-bit
registers or words
Bytes Description
0 Slave address (1 to 247)
1 Function code 0x03
2 Start word address MS byte
3 Start word address LS byte
4 Number of words to be read MS byte
5 Number of words to be read LS byte
6 CRC LS byte
7 CRC MS byte
Bytes Description
0 Slave address
1 Function code 0x03
2 Number of bytes to be read
3 Word 0 MS byte
4 Word 0 LS byte
5 Word 1 MS byte
6 Word 1 LS byte
... …
n CRC LS byte
n + 1 CRC MS byte
Slave no.
Rank (03)
Start register address
No. of 16 bit registers
CRC
1 hexadecimal
byte
2 hexadecimal
bytes
CRC
Slave no.
Rank (03)
No. of bytes
Register data 0
Register data 1
…
1 hexadecimal
byte
2 hexadecimal
bytes

Leroy-Somer POWERDRIVE MD Specifications

General

Brand	Leroy-Somer
Model	POWERDRIVE MD
Category	Inverter
Language	English