Appendix B Pe6000 Modbus Communication Protocol - Pioneer PE6000 Series User Manual

PE6000 User Manual

Appendix B PE6000 Modbus Communication Protocol

The PE6000 series provides RS485 communication interface, and supports the Modbus-RTU
slave communication protocol. You can query or modify the AC drive's function codes, query
various running state parameters, query its faults information through computer and PLC.
J.1 Protocol Content
The serial communication protocol defines information contents and using format transmitted
through serial communication, including host computer polling(broadcasting)format; host computer
encoding, including function code requesting actions, transmitting data and error verify. The
response of slave computer is also the same structure, including action confirm, return data and
error verify. If slave computer breaks down when it receives information or cannot finish the action
requested by host computer, it will organize fault information and feedback to host computer.
J.1.1 Application mode
AC drive will be served as communication slave computer after it is connected to "single host
multi-slave" PC/PLC control net fitted with RS485 bus.
J.1.2 Bus structure
1) Hardware interface
AC drive has RS485 communication interface itself.
2) Topology structure
System with single host and multi-slave: every communication device has a slave address,
among which one device serves as host computer (PC, PLC, HMI etc) and start communication to
write or read parameters in slave. Other devices will respond the host on query or operation of
slave. Only one device can send data while others receive data at the same time.
The set range of slave address is 1~247. 0 stands for the broadcast communication address. The
slave address should be only.
3) Communication transmission mode
Asynchronous serial, half-duplex transmission: In the process of asynchronous serial, data will
be sent in the form of message and 1 frame each time. According to the Modbus-RTU protocol,
when the idle time without data is more than 3.5 Byte transmission time, it means the beginning of
a new frame.
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Appendix B