FX3U-Inverter Modbus Commuinication

[abdoon89]

Hello everyone,

I have a problem connecting FX3U to F700 via Modbus, I wrote a simple program to initialize communication as the example in the communication manual and then programmed the inverter.

I am using the fx3u-485-bd and the built in terminals in the F700, when I started the program, I noticed that the contact M8411 wasn't activated and the Register error D8402 has a value of 201 indicating hardware error. Is it possible to use FX3U-485-bd to start Modbus or I have to bring the Fx3u-cnv-bd with Fx3u-485adp-md?

Thanks in advanced

Edited January 16, 2016 by abdoon89

[abdoon89]

I read the communication manual after I posted this Q and found out that Modbus via rs485 is only supported by the adapter FX3U-485ADP-MB.

 

[Clear.Mind]

On 17.01.2016 at 2:15 PM, abdoon89 said:

I read the communication manual after I posted this Q and found out that Modbus via rs485 is only supported by the adapter FX3U-485ADP-MB.

 

No, fx3u-485-bd can modbus communicating via RS/RS2 instructions, but just 50 meters cable length..

Try to download library  FX3UModbusInverter_GW2_V100 (  For Modbus RTU communication operation of Mitsubishi FR-series frequency inverters, using a FX3U PLC system with a connected FX3U-series serial communication adapter board or special adapter. This FBs are using internally the RS2-instruction )

Or this library FXModbusInverter_GW2_V100 ( For Modbus RTU communication operation of Mitsubishi FR-series frequency inverters, using a FX-series PLC system with a connected FX-series serial communication adapter board or special adapter. This FBs are using internally the RS-instruction. )

Or  FXModbusRTUMaster_V100 ( MODBUS RTU Master functionality for all FX Series PLCs, using serial communication extension boards only (FX1N-485-BD, FX1N-232-BD, FX2N-485-BD, FX2N-232-BD, FX3G-485-BD, FX3G-232-BD, FX3G-485-BD, FX3G-232-BD). The Modbus RTU protocol is internally in the FBs implemented (RS instruction). 

or  FX3UModbusRTUMaster_V100 ( MODBUS RTU Master functionality for FX3U PLCs only, using serial communication modules FX3U-485-BD, FX3U-232-BD, FX3U-485-ADP-MB, FX3U-232-ADP-MB. The Modbus RTU protocol is internally in the FBs implemented (RS2 instruction). 

All this library can communicating with inverters. Last 2 library can communicating with any modbus rtu devices.

 

 

Edited November 26, 2016 by Clear.Mind

[kaare_t]

On 26.11.2016 at 1:12 PM, Clear.Mind said:

No, fx3u-485-bd can modbus communicating via RS/RS2 instructions, but just 50 meters cable length..

The manual states that the module/board doesn't comply with the RS485 standard that's for sure. But in my personal experience (note that I don't guarantee anything) is that the cable length goes way beyond 50m. I've succesfully ran 350m without problems. But again, that's not guaranteed information.