Appendices
Appendix B - MD-BMS and MD-BMED Power Meters Modbus Absolute/Net Value Measurement Registers and
Protocol Commands
89
Building Technologies
125-202
06/06/2017
Example Request Field Name
Command
(Hex)
Response Field Name
Response
(Hex)
Register value to write – low order
bits
00
Register value written – low order
bits
00
CRC low order bits
8C
CRC low order bits
8C
CRC high order bits
5C
CRC high order bits
5C
Command: 3706000000018CSC
Response: 3706000000018CSC
The response is from the power meter at address 37. One byte was written to at the
requested register, 0000. The value written was 0000. The CRC value was 5C8C. An
echo of the original command after the contents are written is a valid response.
Error Response
If the first register in this write command is not in the valid range of registers, the power
meter returns an error message.
Report Slave ID
This command is used to read the description, current status, and other information
specific to a remote device. A normal response includes the data contents specific to
the device.
Table 28: Format for Modbus Command 11 (17 in Decimal).
Command Information
Command Layout
Example Command
Power meter address
nn
37
Command number
11
11
Command Example
Table 29: Example for Modbus Command 11 (17 in Decimal).
Example Request Field Name
Command
(Hex)
Response Field Name
Response
(Hex)
Power meter address
37
Power meter address
37
Command number
11
Command number
11
CRC low or5der bits
07
Byte count
CRC high order bits
8C
Slave ID
Run indicator status
Additional data