If the AS is configured to get the time from an NTP server the customer need to know how often the AS will ask the NTP server for the time.
StruxureWare Building Operation 1.5
In AS version 1.4 the AS asked the NTP server 1 time per minute.
But in version 1.5 this is changed so the AS is using the standard solution for the NPT protocol
When using the standard solution in the NTP protocol as the AS does in version 1.5 it depends on how much the AS drift from the NTP server, the faster the AS drift the more often the time is changed in it