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ENG
“FCR3 three-phase controller” +030222150 - rel. 1.3 - 12.01.2021
9. SUPERVISION
Modbus protocol is supported on serial line V1.0 in slave mode (response
only following query from Master).
Specifi cations
Value
Dip S2.7/ BAUD1
Dip S2.8/ BAUD2
baud rate
9600
OFF
OFF
19200
ON
OFF
38400
OFF
ON
start
1 bit
data
8 bit
parity
None
stop
2 bit
Tab. 9.a
9.1 Modbus
protocol
This is used to manage the connection to all devices and supervisory
systems that support Modbus on serial line V1.0 (specif. V1.1a). The
following table illustrates the currently supported function codes:
Code
Short description
Description
01 (0x01)
Read Coils
Read from 1 to 16 consecutive digital
variables
02 (0x02)
Read Discrete Inputs
Read from 1 to 16 consecutive digital
variables
03 (0x03)
Read Holding Registers
Read from 1 to 16 analogue/integer
variables
04 (0x04)
Read Input Registers
Read from 1 to 16 consecutive analogue/
integer variables
05 (0x05)
Write Single Coil
Write 1 digital variable
06 (0x06)
Write Single Register
Write 1 analogue or integer variable
15 (0x0F)
Write Multiple Coils
Write from 1 to 16 consecutive digital
variables
16 (0x10)
Write Multiple Registers
Write from 1 to 16 consecutive analogue/
integer variables
17 (0x11)
Report Slave ID
Return the MAC identifi er and controller
status
Tab. 9.b
The following table illustrates the currently supported Modbus
exceptions:
Code
Short description
Description
1
Illegal function
Function code not supported
2
Illegal data address
Invalid Slave address
3
Illegal data value
Slave data not valid
Tab. 9.c
9.1.1
Description of the supported function codes
•
0x01 Read Coils
•
0x02 Read Discrete Inputs
Return from 1 to 16 consecutive digital variables.
The slave responds with an exception in the following cases:
EXCEPTION 2:
Address of the fi rst requested variable > 16
Address of fi rst requested va number of variables requested > 16
EXCEPTION 3:
Number of variables requested > 16
•
0x03 Read Holding Registers
•
0x04 Read Input Registers
Return from 1 to 16 consecutive analogue or integer variables
The slave responds with an exception in the following cases:
EXCEPTION 2:
Address of the fi rst requested variable >16
Address of fi rst requested va number of variables requested >16
EXCEPTION 3:
Number of variables requested > 16
Note:
the maximum number of 32 transmittable integer variables
is determined by the maximum size of the transmission buff er.
•
0x05 Write Single Coil
Write a digital variable on the Slave to ON or OFF.
The slave responds with an exception in the following cases:
EXCEPTION 2:
Write variable address > 16;
EXCEPTION 3:
Value to write contained in the Modbus packet other than
0x0000 (OFF) or 0xFF00 (ON)
Note:
a Write Single Coil packet sent from a Master compliant
with the Modbus protocol should NEVER generate this exception;
•
0x06 Write Single Register
Write an analogue or integer variable to the Slave.
The slave responds with an exception in the following cases:
EXCEPTION 2:
Write variable address not between 1-16
EXCEPTION 3:
Data not acceptable by the SLAVE
•
0x0F Write Multiple Coils
Write from 1 to 16 consecutive digital variables to the Slave.
The slave responds with an exception in the following cases:
EXCEPTION 2:
Address of fi rst variable to write >16
Address of fi rst variable to write + number of variables requested >16
EXCEPTION 3:
Number of variables to write > 16
•
0x10 Write Multiple Regsiters
Write from 1 to 16 consecutive analogue or integer variables to the Slave.
The slave responds with an exception in the following cases:
EXCEPTION 2:
Address of fi rst variable to write > 16
Address of fi rst variable to write + number of variables requested > 16
EXCEPTION 3:
Number of variables to write > 16
•
0x11 Report Slave ID
Return the unit code (MAC parameter), the status of the controller (ON/
OFF) and the FW release (REL parameter).
The parameters returned are shown in detail in Table 9.d
The Slave does not respond with an exception in any circumstances.
1
Address
2
Function = 17 = 0x11
17 = 0x11
3
N° Byte
18
4
Slave ID
0
5
Device state
0=OFF / 255= ON
6
MACH
0x01
7
MACL
0x37
8
RELH
00
9
RELL
00
10
HWH
00
11
HWL
00
12
Prot
0
13
Prot
0
14
MAX VARIABLE
0x10
15
MAX COIL INPUT
0x10
16
OPTION CODE
0
17
OPTION CODE
0
18
TV
23/40
19
TI
06/09/12/20/40
20
Customer
0
21
Customer
0
22
CRCH
xx
23
CRCL
Xx
Tab. 9.d