To enable the Scadapack 47x to act as an NTP server for other devices, another NTP server is required to provide the time to the RTU. i.e the x70 RTU will actively look for an NTP server to synch its time, before it provides the time to any NTP Clients.
The NTP Client/Server function can be enabled in the IP Communication >> NTP setting as below. There can be a Primary server and optional standby server (Secondary) to provide the time to the RTU.