Hey all,

I'm working on a project for a customer with multiple G120C VFD's. It has been a while since I have done Siemens work. My quick and dirty question is how to access the status of the G120C's Digital Inputs and how to write a value to the G120C's Digital Outputs? Using TIA Portal v18.

What I am hoping for is some way in the "Device Configuration and Network" to expose the Digital Inputs/Digital Outputs as tags that can be linked within the PLC program; e.g. that TIA Portal has a feature to treat these DI/DQ as part of the PLC's process image and cyclic updates are handled in the background. For my application, the customer just wants to leverage the DI/DQ as if they were a remote rack; e.g. the inputs/outputs of the VFD do not need to act on VFD parameters like Jog Forward, Jog Backward, etc. 

My fear is that this is not possible and I'm going to have to use telegrams and possibly synchronous/async reads/writes with the VFD from the PLC project. 

Any help on this would be appreciated.

Adam.H88

My fear is that this is not possible and I'm going to have to use telegrams and possibly synchronous/async reads/writes with the VFD from the PLC project. 

Your fear is justified. You have to use telegrams. For your reference - The List Manual. 

In general:

• telegram type must be set to the free telegram via p0922,
• status of digitals inputs (r0722) must be assigned to a selected PZD send word via p2051,
• a selected PZD receive word bits must be assigned to outputs - function diagram 2241.

An adequate HW configuration of send/receive telegrams on a controller is also required.