Delta DPM-C510, Operation Manual

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Multi-functional Power Meter DPM-C510 Operation Manual
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5.2 Modbus Communication
5.2.1 Supported Modbus Function Codes
Function
Code
Modbus Name Description
0x03 Read Holding Registers Read the contents of read location
0x06 Preset Single Registers Preset the contents of written location
0x10 Preset Multiple Registers Preset the contents of written loacations
When the protocol is Modbus RTU, the maximum address to be gathered with a single Modbus block read is 50
for function code 0x3, and the maximum address is 49 for function code 0x10. The function code 0xFE can be
used only when the protocol is Modbus RTU.
5.2.2 Modbus Communication Protocol
Modbus RTU mode is adopted with Modbus Master sending out the Request, in which the Function Code uses
0x03 to request response from Slave to correspond to values in Modbus address. In Response, Modbus Slave
responds to the values of Modbus address in the Master request. The packet format of IEEE754 is used for the
address of floating point numbers that corresponds to the register values found in table 5.2, using 2's
complement packet format. The format are as follows:
Low Word
High Byte Low Byte
High Word
High Byte Low Byte
The packet formats (2’s complement) for the address of integers that corresponds to the register values found
in table 5.2 are shown in the example below.
Read ：