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-Master device: Select Set as reference device. The time of the master device can be synced with the NTP server. If the NTP time synchronization of the master device is not enabled, the time of the master device will be synced with the selected time zone.
-Slave device: Enter the group ID of the master device for a slave device. The slave device will be assigned to the same group as the master device.
- GPS: Select a time zone and click Apply.
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