Here is how to handle time zones in ABAP when several time zones are involved in a project. This is quit helpful...
when processes are spread around several regions and/or countries. The time zone should be specified for each user with SU01.
Instead of using the fields SY-DATUM and SY-UZEIT, use the fields SY-DATLO and SY-TIMLO to get local time from the specified time zone for the user.
If you need to convert date and time into a local time zone, the function TZ_SYSTEM_TO_LOCAL should be used.