One Time Reference for Every Node Across Your Power Network

The SMC-300 is an NTP and SNTP Stratum 1 time server. It distributes time over Ethernet using the NTP protocol, which is the standard for SCADA hosts, DCS controllers, historian servers and most IT-side devices in a power utility. The GMC-300 is a PTP IEEE 1588v2 grandmaster. It distributes sub-microsecond time over Ethernet using the PTP protocol, which is mandatory for IEC 61850 process bus substations, merging units and IEDs that require hardware timestamping. Both derive from the same GNSS receiver and UTC reference.

If your substation uses IEC 61850-9-2 process bus merging units or any IED that requires PTP IEEE 1588v2, you need a PTP grandmaster such as the GMC-300. NTP accuracy over a standard LAN is typically in the range of 1 to 10 milliseconds at the client, which is sufficient for SCADA and control room applications but not for protection and control devices that require sub-microsecond synchronisation. If your substation has both IEC 61850 IEDs and conventional NTP clients, deploying one GMC-300 and one SMC-300 from the same GNSS source gives both networks a common time reference.

The SMC-300-R and GMC-300-R incorporate full system redundancy at every critical level: dual GPS receivers, dual master clocks, a comparator unit that continuously monitors both clocks and selects the more accurate one, and dual power supplies. If any single component fails, including the primary GPS receiver, time distribution continues without interruption. The R variant uses Eurocard PCB construction and is recommended for critical bus protection schemes, load dispatch centres and any site where time distribution must be treated as a utility-grade service.

Yes. The SMC-300, GMC-300, SMC-300-D and GMC-300-D all support NavIC-IRNSS alongside GPS, GLONASS, Galileo and BeiDou across L1, L2 and L5 frequency bands with a 184-channel parallel-tracking receiver. For installations in India and the surrounding region, NavIC provides additional satellite visibility that improves lock resilience in urban substations and yard environments where signal obstruction from buildings or structures reduces visible satellite count.

All PreciseSync models include a high-precision OCXO oscillator that activates automatically during a satellite signal outage. The OCXO maintains microsecond-level timing accuracy throughout the holdover period, so NTP and PTP clients continue to receive accurate timestamps without any configuration change or operator intervention. The Rubidium oscillator option provides 0.1 PPB frequency stability with 1 microsecond accuracy sustained over a 24-hour holdover period, which exceeds the requirements of most grid-code compliance frameworks.

A single SMC-300 or GMC-300 can distribute time to an unlimited number of NTP clients or PTP slaves over the station Ethernet LAN, and simultaneously distribute IRIG-B to connected relays, disturbance recorders and RTUs via coaxial or fibre outputs. For sites with high availability requirements, the R variants provide component-level redundancy within a single unit. For very large generation plants or switching stations with multiple independent protection zones, deploying one SMC-300 and one GMC-300 from the same antenna feeds is the recommended architecture.