Hello David;

The Sick ATM 60 is an absoliute encoder, designed for 8192 counts/rev, and 8192 revs, Which gives you a maximum of 16,277,216 counts.

First, an absolute encoder retains its last value on power off, when you power back up it should give you the same reading (if the system has not changed its position).

Second, a rollover happens when you excedd eiter you maximiun or minimum number of counts, and you must prepare for it when you parameterize the encoder (see the screenshot below), and when your PLC program detects the transition.You must then determine what you want to do for your count value when your encoder gives you a transition from 16,277.216 to 0... For example, do you want to increase the count abpve the limit value f 16,277,216 given by the encoder, then add the new count (starting with 1) to the maximum count value when you detect rollover, until you exceed the DINT datatype limits (+2,147,483,647, which should last a while).

Look at the Operating instructions for your encoder, which you can download from this Sick webpage:

https://www.sick.com/ca/en/encoders/absolute-encoders/atm60/atm60-p4h13x13/p/p289256

Hope this helps,

Daniel Chartier

At first: I don't know the encoder you have, have not looked it up.

If this encoder offers Telegram 81 or 83, then just connect this to the technology object via PROFIdrive. It cannot get any simpler than this, as the TO then handles all the communication via telegram, including interpretation of the data.

If the encoder does not offer these telegrams, then using DB connection is the right solution.

BUT: The technology objects expects everything to be according to PROFIdrive! Data as well as state-machine. So you would need to "translate" between the data of your encoder (provided to the DB) and PROFIdrive, so that the data in the DB to which the TO is connected is according to PROFIdrive.

Depending on what the encoder provides, this might be quite some work to do!

Luckily there is an application example that contains an FB which does this for you: https://support.industry.siemens.com/cs/de/de/view/109741575/en

Just use the FB SimpleEnc from this example, this will do the trick. But pay attention to the information in the documentation about this, not only about what to connect to the FB, but also about how to parametrize the TO when using this solution! You really need to do everything like described, otherwise it will not work.