can be compared with each other. With time synchronization, events anddisturbances within the whole network, can be compared and evaluated.In the IED, the internal time can be synchronized from the following sources:• BIN (Binary Minute Pulse)• DNP• IEC103• SNTP• IRIG-B• SPA• LON• PPS• IEEE 1588 (PTP)Out of these, LON and SPA contains two types of synchronization messages:• Coarse time messages are sent every minute and contain complete date andtime, that is year, month, day, hour, minute, second and millisecond.• Fine time messages are sent every second and comprise only seconds andmilliseconds.The selection of the time source is done via the corresponding setting.If PTP is activated, the device with the best accuracy within the synchronizinggroup will be selected as the source. For more information about PTP, see theTechnical manual.IEEE 1588 (PTP)PTP according to IEEE 1588-2008 and specifically its profile IEC/IEEE 61850-9-3for power utility automation is a synchronization method that can be used tomaintain a common time within a station. This time can be synchronized to theglobal time using, for instance, a GPS receiver. If PTP is enabled on the IEDs andthe switches that connect the station are compatible with IEEE 1588, the stationwill become synchronized to one common time with an accuracy of under 1us.Using an IED as a boundary clock between several networks will keep 1usaccuracy on three levels or when using an HSR, 15 IEDs can be connected in a ringwithout losing a single microsecond in accuracy.18.12.2 Setting guidelines IP15089-1 v3All the parameters related to time are divided into two categories: System time andSynchronization.18.12.2.1 System time M11348-119 v5The time is set with years, month, day, hour, minute, second and millisecond.1MRK 504 169-UEN A Section 18Basic IED functionsTransformer protection RET650 2.2 IEC 355Application manual
