kaare_t

Yes, the IO number and the head address both depend on what modules are placed between the CPU and the specific module you wish to get the address for. So if you have the MB91 directly to the right of the CPU, it will have the starting address h00. If you have an ethernet card between, the MB91 will have the start address h20.... You can also freely assign the starting addresses in the IO setup under PLC Parameter. You can choose freely which addresses you want to assign to each card, but I would recommend to stick with the default values (which are automaticly assigned if you don't write anything there). Head address is simply the start IO address except for the last number (IO h00 = HeadAddr 0, IO h20 = HeadAddr 2, IO h50 = HeadAddr 5)

RS485 is always a bit difficult since there's no 'standard' when naming the connections (as you've discovered with your devices). There should be no problem in "testing" different cabling, so you can try to see if one polarity works. If it don't work you have to reverse it.... Just don't connect any power supply to the bus cable....

It's hard to say if the converter needs 5VDC (or 12VDC or 24VDC) but most likely it has to be powered....

You can use cheap RS232/RS485 converters to connect several RS232 devices. You will need 1 converter per slave, and you must ensure that each slave has it's own unique station number (Slave number / station number / slave ID). See attached picture.

Are you sure that your F2-20GF works? Have you set the PLC in STOP (you cannot "online-stop" the F2 PLC, you have to physically set the PLC in STOP mode)?

I'm not sure how Mistubishi Australia handles these kind of issues but I think you'd better call your local distributor and check how this can be solved....

Screenshots of both parameter setup and transfer setup would also be good to help us help you.....

What do you mean "Running 2 PLCs together"??

Hi. As long as you are a slave in the Mitsubishi you don't need to "send" any data. The module will automaticly generate the correct response when a request is received. The devices in the Mitsubishi CPU are allocated to specific Modbus devices, take a look in the manual under chapter 6.4 (Device Allocations).

I don't remember if GX Developer has the same menu as GX IEC Developer, but I think you have to: 1. Add an intelligent module under PLC Parameter -> IO assignment 2. Go to "Module Configuration", select the correct module and press "Configure Module" You should then be able to select the correct module As mentioned I don't remember if the menu's are the same, but the above works for GX IEC Dev.

GX Configurator MB should be included in your GX Developer license. If you have a CD it should be included there under "Utilities" (if I remember it correct). Yes, it's much easier to set up the cards if you use GX Configurator MB. You can do it with PLC programming, but then you'll have to set up and configure the cards using PLC code which is a bit of work. However with GX Configurator MB you can simply configure the cards via a windows GUI. I would recommend to install GX Configurator MB!!

1. Yes, you need to set up one of the Modbus cards as master, and the other card as slave 2. Correct 3. You must install GX Configurator MB to configure the modules

RS485 are sometimes a bit confusing since different vendors name the pins in different ways.... You'll just have to try the different connections, and possibly also try to switch + and -....

Strange..... Are you sure that the slave device is a RS232 device??

You also need one wire for the ground (PIN 5).....

Let us know what Mitsu says then, so that we know what the problem was (and forum users can see the solution in the future)

If you're going to communicate via ModbusRTU (either as a slave or as a master) you should check out the already published function blocks (GX IEC Developer) for this purpose..... http://www.beijer.no/web/web_aut_no.nsf/docsbycodename/filearchive?OpenDocument&mylink=/web/BExFilePileAUT.nsf/fm.be.searchframe?Openform&Lang=NO&DocID=1072A50FA9CEEAE9C12573C4004E3A25

Check out ModScan32 for debugging Modbus comm. You can download it from their website: http://www.win-tech.com/html/demos.htm I know it's an old software, but it's really (REALLY) simple to use and does it's job.

Hi again. Check out this function block. I know the function block is for BD card, but RS and RS2 are quite similar, so check out the function block and maybe you can use/modify something in your application. http://www.beijer.no/web/web_aut_no.nsf/docsbycodename/filearchive?OpenDocument&mylink=/web/BExFilePileAUT.nsf/fm.be.searchframe?Openform&Lang=NO&DocID=46B82E00767FA7A1C125728E005D1FBA

What software do you use?

Do you always write your code in IL, or have you just copied the IL code from your programming tool?? Do you have the possibility to post the code in ladder (GX Developer/GX IEC Developer/GX Works)?

Have you tried to install the software GX Developer / FX Configurator with the antivirus and firewall turned off?? I know you've said that you have tried to switch off the firewall/antivirus while trying to communicate, but did you try to turn it off before installation??

Have you set up TCP communication in GX Developer (see picture)??

You cannot run the 'standard' Modbus/TCP on the FX3U-ENET. Standard Modbus port number is TCP-502 (this is the official assignet port number for Modbus/TCP), and the FX3U-ENET cannot open any ports below 1024! So unless you can assign your own ports for the Modbus/TCP device(s) you are going to communicate with you have a big problem.....

The address of the special function modules on the FX-series start at 0. So if your ENET module is placed directly on the right side of the PLC, the address will be 0. If you have some other module first, then the ENET module, it will have the address 1 and so on..... Try to correct your program (U*) and see if you get operation errors...