Leroy-Somer PROXIDRIVE, Руководство для продвинутых пользователей

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117
ADVANCED USER GUIDE
PROXIDRIVE
IP66 variable speed drive
OPERATION WITH MODBUS RTU
LEROY-SOMER
3756 en - 05.2004 / b
1 1 0 0 . . 4 4 0 0 : Status word 19.4 - MODBUS RTU
19.4.1 - General
The MODBUS RTU protocol is a master-slave type protocol
(individual master for each network).
Note: If the CT Comms cable is used, the baud rate is limited
to 38400 bauds.
19.4.2 - Description of exchanges
Exchanges are initiated by the master, which transmits its
request: if the slave concerned has understood it, it sends its
response. Each frame (question or response) contains four
types of data:
- the address of the slave concerned which receives the
question frame (master request) or the address of the slave
which sends the response frame (encoded on a byte)
- the function code which selects a command (read or write
words, bits etc) for question and response frames (encoded
on a byte)
- the data field containing the parameters relating to the
command (encoded on "n" bytes)
- the frame CRC, calculated on sixteen bits, which is used to
detect transmission errors.
The frame is terminated with a minimum silence period of 3.5
character times (for example, at 19200 baud the minimum
silence period is 1/19200 x 11 bits x 3.5, ie. 2 ms). This
silence period indicates the end of the message, and the
slave can begin processing the transmitted data.
All data is coded in hexadecimal format.
Status
word bits
1
1
0
0
.
.
4
4
0
0
Corresponding
parameters
Drive status
0 1
1
0
0
.
.
0
0
1
1
Drive healthy
1 1
1
0
0
.
.
0
0
2
2
Drive active
2 1
1
0
0
.
.
0
0
3
3
Zero speed
3 1
1
0
0
.
.
0
0
4
4 Running at or below min speed
4 1
1
0
0
.
.
0
0
5
5
Below set speed
5 1
1
0
0
.
.
0
0
6
6
At speed
6 1
1
0
0
.
.
0
0
7
7
Above set speed
7 1
1
0
0
.
.
0
0
8
8
Load reached
8 1
1
0
0
.
.
0
0
9
9
Drive output is at current limit
9 1
1
0
0
.
.
1
1
0
0
Regenerating
10 1
1
0
0
.
.
1
1
1
1
Braking IGBT active
11 1
1
0
0
.
.
1
1
2
2
Braking resistor alarm
12 1
1
0
0
.
.
1
1
3
3
Direction commanded
13 1
1
0
0
.
.
1
1
4
4
Direction running
14 1
1
0
0
.
.
1
1
5
5
Mains loss
Description Characteristics
Normal physical layer for
multi-drop operation RS485 2 wire
Bit stream Standard UART asynchronous
symbols with Non Return to
Zero (NRZ)
Symbol Each symbol consists of:
1 start bit
8 data bits (transmitted least
significant bit first)
1 or 2 stop bits depending on
1
1
1
1
.
.
2
2
7
7
Baud rate 300, 600, 1200, 2400, 4800,
9600, 19200, 38400, 57600,
115200 bauds
Slave Function
Message data
16 bit Silence
address code CRC interval
All master requests will lead to a response from an individual slave. The slave will respond within the maximum allotted time (the
minimum response time is never less than the silence period).
Master request Master request
Frame detect
Slave frame
Processing
Minimum silence period
Slave
response time
Slave response
Minimum silence period