Chint DDSU666 Modbus register map
Also covers DDSU666.004.0006
Single-phase DIN-rail energy meter with RS485: voltage, current, power, power factor, frequency and import/export energy
- Official
- 15 registers
- Modbus RTU
- Revision 3 · 2026-10-18
Official: Written from the manufacturer's documentation, but not tested on a device yet. Check the map against the manufacturer's documentation before you write to a live device. Tested it? Report a test.
Communication
- Protocol
- Modbus RTU
- Unit ID
- 1
- Serial
- 9600 8N1 · 9600 baud, 8 data bits, none parity, 1 stop bit
- Byte / word order
- ABCD · bytes big-endian, words high first
- Addresses
- 0-based
Connection values are defaults: the device may be configured differently.
Map
- Registers
- 15 holding registers
- Groups
- 4
- Revision
- 3 · 2026-10-18
- Added
- ()
- File
- maps/chint/ddsu666.mbmap.json · 4 KB · history
- SHA-256
- 6c1522da93a1e33e2dc8e422cee21999db61066200010749cd0687b70c0785e0
- Manufacturer
- chintglobal.com
Sources and notes
- DDSU666 Single-phase electronic type guide rail mounting electric energy meter, User manual · version ZTY0.464.922 parameter tables, including meter type and reverse energy
- DDSU666.004.0006 type single phase electronic energy meter (DIN-Rail), Operation manual · version ZTY0.464.1036 parameter tables and appendix A
Source: Chint, DDSU666 single-phase electronic energy meter (DIN-rail) manuals ZTY0.464.922 and ZTY0.464.1036, appendix A (MODBUS-RTU)
- Function codes 03 (read) and 10 (write multiple registers). The meter ships with the DL/T 645-2007 protocol: write 2 to the Protocol register to switch to Modbus-RTU.
- Floats are IEEE 754 single precision, high word first. Values are on the secondary side and already in engineering units.
- Frame format: 8 data bits and no parity; the manual's appendix says two stop bits ('other formats can be customized'), while the display example shows one stop bit. The map uses one stop bit.
- The baud rate table lists 2400, 4800 and 9600; the text also mentions 1200.
| Area | Address | Name | Type | Access | Unit | Scale | Description |
|---|---|---|---|---|---|---|---|
| HR | 0 | uint16 | RW | Programming password | |||
| HR | 1 | uint16 | R | Reads the version number | |||
| HR | 2 | uint16 | RW | ||||
| HR | 5 | uint16 | RW | The meter leaves the factory on DL/T 645; write 2 to use Modbus-RTU | |||
| HR | 6 | uint16 | RW | ||||
| HR | 11 | uint16 | R | ||||
| HR | 12 | uint16 | RW | ||||
| HR | 8192 | float32 ABCD | R | V | |||
| HR | 8194 | float32 ABCD | R | A | |||
| HR | 8196 | float32 ABCD | R | kW | |||
| HR | 8198 | float32 ABCD | R | kvar | |||
| HR | 8202 | float32 ABCD | R | ||||
| HR | 8206 | float32 ABCD | R | Hz | |||
| HR | 16384 | float32 ABCD | R | kWh | |||
| HR | 16394 | float32 ABCD | R | kWh |
No registers match
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Help improve this map
- I tested it on a deviceReport whether it worked, even if you did not write the map.
- Suggest a correctionEdit the file on GitHub; it opens a pull request.
- Report a problemA wrong address, type, scale or byte order.
- Read the formatWhat each key of the file means (SPEC.md).