Field help (TIMSPGDAY2) 

The timestamp entry is used to enter the time devoted to the processing of a service request.
Each entry of a new timestamp triggers the calculation of the total time for the different timestamp entries, as well as the new consumption carried out.

The product, which is automatically consumed for this timestamp, is defined in the setup. (Products for timestamp)

Each timestamp can be entered manually. They can also be calculated automatically if you click Start timestamp from the Actions icon.

Each time a timestamp is triggered, it is automatically recorded if one of the following events occurs after one minute:

The timestamp triggered from one of these three fields is related to the default installed base.

You can also click Start timestamp from the Actions icons available on each installed base concerned when the timestamp relates to a specific base.

The triggering of a timestamp is also the means to access specific operational features of the service request processing.

The Preferences action is indeed used to activate the access to a specific feature in the context of the service request.