If devices are optional or sometimes used and sometimes not used, and you want a single PLC project application, then configuration control is essential.  For that, I recommend downloading at least 1 sample application, preferably every sample application you can find, and try it out.

You can have optional remote I/O, and optional local I/O, and different / optional modules within any I/O rack.  For the most flexibility, you will want to use an s7-1500.

For 10 PN devices, you are already into the realm of s7-1500, or the S7-1200 G2 (assuming it is fully available to you in your region and with all required support hardware for your projects).

For TC connections left unused, it is strongly recommended to jumper them.  Without the jumpers - at least for s7-1200, you will get errors with your connected TCs near the un-jumped TC connections.  For example, let's say your application uses TC 1-4, and TC 8 within a given TC AI module.  That would mean in real-world applications, you may see impacts to TC 3 & 4, and almost definitely TC 8.

Reason is that the s7-1200 TC AI module uses a multiplexed A/D conversion, and the floating TC inputs eventually raise the signal high enough that the multiplexor does not settle down in time to read adjacent channels.  Typically, it is channels _after_ the open channels, but I have seen it both before and after those open channels.

Is this information at all useful?  Hope it is but if not, perhaps it will help others.

On every s7-1200 TC project, I force all un-used TC inputs to be jumped.  Otherwise, the system raises an alarm and will never go into auto mode.

99Paul

I have varying Hardware configurations. F. e. Some customers want to monitor certain additional Temperature values. Can the Wire break Protection be switch on and off inside the PLC Software? If the channel is not used and the Protection is switched of the system delivers floating Temperature Values. We have got over 10 ProfiNet Devices in the Machine. Some of those are not always necessary and then not connected. .