DDS661 LCD Digital Display Consumption Meter
Specifications:
- Communication Protocol: MODBUS-RTU
- Data Format: Address + Function Code + Data + CRC Check
Code - Data Description Format: 32-bit 4-byte single-precision
floating-point number data format
Product Usage Instructions:
Reading Meter Parameters:
To read meter parameters, follow these steps:
- Prepare the data to be sent in the format: Address + Function
Code + Data + CRC Check Code. - Send the prepared data to the meter.
- Receive and interpret the return data in the specified
format.
Modifying Meter Address:
To modify the meter address, use the following command:
- Prepare the command data with the new meter address.
- Send the command data to the meter.
- Check the return data to confirm the address modification.
Modifying Communication Rate:
To modify the communication rate of the meter, follow these
steps:
- Create the command data with the new communication rate.
- Transmit the command data to the meter.
- Verify the return data for successful rate modification.
FAQ:
Q: What is the data format for reading meter parameters?
A: The data format for reading meter parameters
is Address + Function Code + Data + CRC check code.
Q: How do I modify the meter address?
A: To modify the meter address, issue the
appropriate command with the new address and verify the return data
for successful modification.
RS485 Communication Meter Reading Application (Communication
Protocol) and Register Addresses
This energy meter can realize long-distance reading and recording of electricity in the meter through its RS485 interface. The meter can also be used to read the power data in the meter from a Pocket PC through its infrared communication interface in a short distance. The coding format, checksum (even parity) and data transmission mode (eight data bits and one stop bit) are in accordance with MODBUS-RTU standard. The default baud rate is 1200bps, 2400bps, 4800bps, 9600bps (default) is optional. If there is no special requirement, the meter is set according to the default baud rate of 9600bps from the factory, and you can modify the meter address and communication rate through the software provided by us.
MODBUS-RTU communication protocol description:
1. Data format: Address + Function Code + Data +CRC check code
2Example of reading meter parameters: For example, if you need to read the meter address 01, data start
address 00 current A phase voltage data, you need to enter the following data: (1) Sending data: 01 04 00 00 00 02 71 CB
Data description: Data Detailed description 01 Instrument address 04 Function code, reads data from the meter’s internal registers 00 00 Read data from the meter’s internal register address starting at 00 00 00 02 Read data length, 2 words and 4 bytes of data
CRC check of the previous data, where the high bit comes first and the 71 CB
low bit comes second
(2)Return data: 01 04 04 43 6B 58 0E 25 D8
Data description:
Data Detailed description
01
Meter address
04
Return function code
04
The data length returned is 4 bytes of data length
43 6B Returned data, 4 bytes in length
58 0E
25 D8 CRC checksum returned
(3) Data format description: The read data inside the meter conforms to IEEE-754 standard
floating-point number, and the data format is 32-bit 4-byte
single-precision floating-point number data format.
3. Modify the meter address:
Command to modify the meter address: for example, to modify the
meter address to 02, the following command is issued: 01 10 00 08 00
02 04 40 00 00 00 E7 C9
Data Description:
Data
Detailed description
01
Meter address
10
Function code, writes data to the meter’s internal registers
00 08 Write data from the meter’s internal register address 00 08
00 02 Write data length, 2 words, 4 bytes of data
04
Write data length, 4 bytes of data
40 00
Table address of the table to be written, 4 bytes of data, floating-point data
00 00
E7 C9 CRC Checksum
Return data: 01 10 00 08 00 02 C0 0A 4Modify the communication rate of the meter:
Command to modify the communication rate of the meter: For example,
if the communication rate of the meter is changed to 1200bps, the
following command is issued: 01 10 00 00 00 02 04 44 96 00 00 07 73
Data Description:
Data
Detailed description
01
Meter address
10
Function code, writes data to the meter’s internal registers
00 00 Write data from the meter’s internal register address 00 00
00 02 Write data length, 2 words, 4 bytes of data
04
Write data length, 4 bytes of data
40 96
Table address of the table to be written, 4 bytes of data, floating-point data
00 00
25 7B CRC Checksum
Return data: 01 10 00 00 00 02 41 C8
In the MODBUS protocol, the function code 0x04 is used to read meter data, with the register addresses as follows:
Data description:
Address (Hex)
Register Parameter Description
HI L0
Description
Unit
Format
Mode
00 00
Voltage
Volt
Floating Point
Read Only
Floating 00 08 electric current amperage
Point
Read Only
00 12
Active power
Floating Kilowatts
Point
Read Only
00 2A
Power factor
Floating
COS
Read Only
Point
00 36
frequency
hertz Floating (physics) Point
Read Only
Kilowatt- Floating
01 00 Total active power
hours
Point
Read Only
Use function code 0x03 to read the meter parameters or function code 0x10 to modify the parameters with the following register addresses:
Address (Hex)
Save Register Parameters
Length
HI
L0
Format
(bytes)
Description
Unit
Mode
00
00
Floating Baud rate (1200 2400 4800
4
bps Read/Write
Point
9600)
00
02
Parity bit (0: Even
Floating
4
parity; 1: Odd parity; 2:
Point
No parity)
Read/Write
00
08
Floating Correspondence address not
4
Read/Write
Point
(Form No. 1-247)
have
Documents / Resources
 |
DDS DDS661 LCD Digital Display Consumption Meter [pdf] Instructions DDS661, DDS661 LCD Digital Display Consumption Meter, DDS661, LCD Digital Display Consumption Meter, Digital Display Consumption Meter, Display Consumption Meter, Consumption Meter |