SEDEMAC GC1100, Руководство пользователя, Страница: 54 / 70

GC1100 SEDEMAC
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Precautions
•
Keep the slave ID of the GC1100 controller and SMPS same, take the slave ID from the SMPS
and configure the same ID in GC1100.
•
Enable the GC1100 in the configuration of the SMPS after hardware connections are made, so
the SMPS can communicate with the GC1100.
•
Connect the Pin # 16 & 15 (A & B) of the GC1100 to the pin # A & B of the SMPS respectively
and not with any other pin.
•
Use two core shielded cable for connection.
•
Use different colour wires for Pin # 16 & 15 (A & B) for easy detection and connection.
•
Route the Pin # 16 & 15 (A & B) wires properly ensuring they do not get short with any other
wires.
•
Do not use multi strand wires for the connection.
12.3
Function Code Used
Function code is a part of MODBUS message that defines the action to be taken by the Slave.
SEDEMAC GC1100 supports following functions;
Table 31: Details of function codes
Function Code MODBUS Name Description
03
Read holding
register Reads one or more 16-bit from the slave device of read/write
location
04 Read input register
Reads one or more 16-bit from the slave device of read/write
location
16
Write holding
register
Writes one or more 16-bit registers to the slave device
Supported functions and respective command-response structure is as shown below. If the command
received from the MODBUS master is other than the three functions mentioned below, an exception
message is generated.
Function 4 (0x04): Read Input Registers
This function is used to read measurement parameters and status from the genset controller. The
command-response pattern is as shown in
Table 32
and
Table 33
.
Table 32: Command from MODBUS master for Function 4
Byte Field Remarks
0 Slave address As configured in genset controller
1 Function code (0x04)
2 First register address – high byte
16-bit register address, register address map
is described in
Table 38 3 First register address – low byte
4 Number of registers to read – high byte
Number of registers to read must be between
1 to 255
5 Number of registers to read – low byte
6/7 Error check CRC
Table 33: Normal response from genset controller slave for Function 4
Byte Field Remarks
0 Slave address As configured in genset controller
1 Function code (0x04)
2 Byte count (n)
Equals to number of registers to be read times