Mitsubishi PLC <> Profibus I/O modules

Hello !

I have problem with digital inputs in Q12H PLC, maybe sombody from You can help me.I am rather not familir with mitsubishi PLC.

Problem is that i am using I/O modules as a basic modules on PLC rack (addreses 0030-00F0) and Siemens IM153-1 modules on Profibus conection (addresses 0100-0380). All signals from mitsubishi modules are working properly but those from probibus connection in range 0100-0300 are not working in fact. It means - a can see status in online mode but even if status of digital input is "1" it don't affect on function - is "0". I can monitor this signal in Variable tabel and i see how status is changing when i switch off/on fuse but still not working in software.

"1" "0"
----[x100]------------------(M3)

Do you maybe know if there is some address range which cannot be use for such modules or maybe this is problem of Profibus configration or something?
Any help? Please!?

Pawel S.

This sounds like a very strange problem.

The address range you are using should be alright if it does not conflict with any other hardware.

Can you see the input come on when viewing the ladder program online?

How are you transferring the profibus master module's buffer memory to the X devices? Is it by the auto refresh function in GX Configurator DP or by a FROM instruction?

What about outputs, do they work?

Mitsubishi manuals can be very confusing to read (a bit of an understatement!), but I would advise you to read the manual for the profibus module very carefully. There might be something you missed during configuration.


Good Luck

Yes, it is very strange. I can see status in ladder program, i can see how it change when i switch it on/off. I am trying to read all manuals - for PLC and Profibus module and nothing i can find.
I am using GX Configurator-DP to download the hardware configuration, and i am using Automatic Refresh. My configuration form Rack is:
SLOT Type Address
PLC PLC -
0 Intell. (PB92D) 0
1 Intell. (Melsecnet) 3A0
2 Intell. (Ethernet) 3C0
3 Input 30
4 Input 40
5 Input 50
6 Input 60
7 Input 70
8 Input 80
9 Input 90
10 Input A0
11 Input B0
12 Input C0
13 Output D0
14 Output E0
15 Output F0

And first address in profibus configuration is X100 for IM 153-1 module. I think it should works but maby i made some mistake?
Maybe i should add something in software for profibus transfer, because i just start it by setting Y0:
------[SM400]--------------------(Y0}

What do you think it is enought?

Slot addresses should be consecutive

The I/O addresses for installed modules should be consecutive.

In your case:

SLOT, Type, Number of I/O points, Address(hex)
0 , Intell. (PB92D), 32, 0
1 , Intell. (Melsecnet), 32, 20
2 , Intell. (Ethernet), 32, 40
3 , Input, 16, 60
4 , Input, 16, 70
5 , Input, 16, 80
6 , Input, 16, 90
7 , Input, 16, A0
8 , Input, 16, B0
9 , Input, 16, C0
10, Input, 16, D0
11, Input, 16, E0
12, Input, 16, F0
13, Output, 16, 100
14, Output, 16, 110
15, Output, 16, 120

This means that you can't use X100 for your profibus auto-refresh. Try starting you profibus auto-refresh addresses from X300 this will give you plenty of space to add new I/O modules to your PLC.

The manual that explains I/O assignment in Q series PLCs is "High Performance Model QCPU(QMode) User's Manual (Function Explanation, Program Fundamentals)", Manual Number SH(NA)-080038-F.

Best Regards

Thank you for your responce!
It really looks like you said because i remove those two intll. modules and then it is working even if i leave setting for rack for this two places - empty slot - with old addresses. Only when i put one of this modules it stop working.
Problem is that i was trying to assign addresses to already existing project but programmer did not provide for setting of PLC.

I will try once again with concequence address setting and we will see.

Best Regards

Pawel S.