Hi, 

The update collections consist of updates for several software such as CFC, Batch, RC and also WinCC updates.

It really depends if you can install the UC on separate stations.

You should look in the readme of the latest update collection to check the history. All software that has received an update is listed. Readme UC05 for PCS7 V9.0 SP3 

For example if you have a OS client and UC01 to UC05 has only updates for the current WinCC version, then you can manage to install on the servers and ES without clients, but if the WinCC has received a new service pack, you must install it on all OS stations in order to work properly. It complicates things if you also have RC or Batch because you need to take that into account as well.

Another option is to install the updates separately by yourself from the website. On the website you see a small number behind the name of the software, which indicates in which UC it is included. Only the latest updates are available for download.PCS7 V9.0 SP3 software updates