Dear all,

has anyone implemented any project including communation between siemens logo and ac drive altivar ATV630?

Is there a solution to the problem that the modbus address range of siemens logo is for VW 0-850 that is mapped in holding registers 1-425 and the two important registers for controlling operation of ATV630 are 8501(command) and 8502 (frequency reference) ?

Could this be tackled somehow or is it not feasible?

Kind regards

Hi,

this is maybe an misunderstanding.

In LOGO! the VM memory is to exchange data with other devices. Do you realy need all register of your device in LOGO!?

In normal cases just a view registers are needed in LOGO! and so you configure the registers and the target VM-Memory in the modbus data table:

Here an example: 

You can transfer the value of the configured Modbus register (4024) to the specified VM-Memory adress (VW10) in LOGO!.There is no need to transfer other is this the only information you need.

LOGO! offer only 850 bytes of memory to do so.

Hope this helps

Hello.

Thanks for your reply.

Yes, of course I do not need all the registers of my device to logo.

I only need 8501(command) and 8502 (frequency reference).

However, as it can be seen in the attached picture about the logo modbus address space, the mapped modbus address range for address type VW, consists of registers 1 to 425, while I want only the two registers 8501 and 8502.

Ok, understood.

However, I have made the configuration seen in the image attached(which is similar to the one you made) and there is no communication between the logo and altivar.

Actually, I see in the communication map of the altivar that there are frames of communication between the two but neither the command word nor the frequency reference register have values.

Also, if there is an offset+1 in logo modbus addresses, would the right addressing be 8502 (for 8501 register) and 8503 (for 8502 register)?

Have I not understood it right?

Ok, problem solved!

Two critical points:

1) I had to put 248 as unit ID, not the default 255.

2) An offset of +1 needed. i.e. for 8501 command register, 8502 is needed to be put in the ethernet connection pop-up window.

The system runs without any problem.

Hello

Could you please share your project? I'm trying to learn same issue

Many thanks

Hello

Could you please share your project? I'm trying to learn same issue

Many thanks

lamplamprop 87

Ok, problem solved!

Two critical points:

1) I had to put 248 as unit ID, not the default 255.

2) An offset of +1 needed. i.e. for 8501 command register, 8502 is needed to be put in the ethernet connection pop-up window.

The system runs without any problem.