LS SV-xxx-iP5A-2, Руководство пользователя

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Chapter 8
– RS485 Communication
8-4
3) If computer is a master, RS232-485 converter is needed to communicate
because computer does not have RS485 port.
The communication is delayed at transmitting/receiving when the RS232-485
converter is used. If delay is happened, retry the communication by increasing
the I/O-94 [Delay Time].
4) Operate the inverter using the operating program for the inverter.
5) Refer to
‘Chapter 6. Trounbleshooting and Maintenance’ if the communication is
not operating normally.
6) User program or the
‘DriveView 7’ program supplied from LS Industrial Systems
can be used as the operating program for the inverter.
7) Turn the inverter J3 switch ON to connect the terminating resistor for the end of
network.
* Connect to C+,C-,CM terminal on the control terminal. Be careful for the
po, -).
* Maximum connectable inverter are 31.
8.4 Communication protocol (RS485)
The configuration of RS485 is that PC or PLC is the Master and Inverter Slave.
Inverter responds the Master’s Read/Write Requests.
When master sends Write Request to Inverter address # 255, all inverters perform
Write action but do not return a Acknowledge response. This is used to drive
multiple inverters at the same time via RS485.
8.4.1 Basic format
1) Command message (Request):
ENQ Inverter No. CMD Data SUM EOT
1 byte 2 bytes 1 byte n bytes 2 bytes 1 byte
* Normal response (Acknowledge Response):
ENQ Inverter No. CMD Data SUM EOT
1 byte 2 bytes 1 byte n * 4 bytes 2 bytes 1 byte
* Negative response (Negative Acknowledge Response):
ENQ Inverter No. CMD Data SUM EOT
1 byte 2 bytes 1 byte 2 bytes 2 bytes 1 byte
Request
Frame
Response
Frame
I/O 94
[Communication
response delay time]
Master
Slave
(Inverter)