Hello Jan;

I am not a Danfoss specialist, so take my answer  with a grain of salt and validate my comments with Danfoss documents.

PPO is a telegram structure for Profidrive over Profibus. It is a structured telegram format that you select when you are configuring the drive as a Profibus slave, similar as when you select a specific telegram for profinet. A syuch, it does not appear once configuration is finished, except fror the number od data registers selected and the liked register addresses in the CPU memory.

If you look at the PPO selection for MCA 101 (Profibus adapter for FC 302) in the attachment below, you can see how selecting one specific PPO type will affect the size and data content of the exchange with the Profibus master. If you select Danfoss telegram PPO1, you are reseving 4 words to read and write parameter valiues to the drive, and using only 2 words for process values; the control word and the speed setpoint. If you choose PPO6, you have no access to read/write parameter values, and you reserve 6 words for process values: control word, speed setpoint, and 4 words for drive values at you choice: torque, current temperature... Details on the contents of the PPO registers are found here:

https://files.danfoss.com/download/Drives/MG37G202.pdf

So there is no"online" connection with the PPO itself once the configuration is done. One example of what you can do for example is setup a monitoring table in the PLC programming software to check the values transfered over the reserved addresses generated by your selection of a particular PPO. Or if there are any communication issues with the drive, the CPU's diagnostic buffer will capture the fault (with more information if you have OB 86 inserted in your program) and you will be able to determine the issues faulting the communications.

Hope this helps,

Daniel Chartier