A digital slave clock is a display clock that doesn't keep its own independent time — it continuously synchronizes from a master clock or an NTP time server, so every clock in a facility shows exactly the same time without manual adjustment. Because the clock relies on an external time reference rather than its own crystal alone, drift is corrected automatically and time corrections reach every unit at once.
Shown with a red display in HH:MM:SS format. Also available in blue and green, in 2 to 12 inch digit sizes.
Three connection options
Our ORNATE 7500 Series slave clocks are available in three connection variants so you can match the clock to your site's existing infrastructure:
ORNATE 7500 SNTPE — powered over Ethernet (PoE). A single Ethernet cable carries both power and NTP time sync, so installation is one RJ45 drop per clock with no separate power adaptor.
ORNATE 7500 SNTRJ — an Ethernet slave clock that connects over standard RJ45 for NTP sync but runs on its own independent power supply, useful where power and data need to stay on separate circuits.
ORNATE 7500 SNRF — synchronizes wirelessly over RF from a master clock, with no data cabling at all. This is the fastest option to deploy in retrofit buildings or anywhere pulling network cable to every clock location isn't practical.
All three come in blue, red and green displays, HH:MM or HH:MM:SS format and 2 to 12 inch digit sizes. The ORNATE NT-156 is a further PoE/RJ45 LED slave clock with NTP/SNTP synchronization and a battery-backed real-time clock.
Where slave clocks are used
Network slave clocks are common in schools, hospitals, railway stations, airports, factories and office buildings — anywhere multiple clocks need to be visible and in agreement, without staff manually resetting each one after a power cut.
Choosing a connection type
If your site already has PoE switches with spare ports, SNTPE is the simplest install. If your network is data-only but you have separate power circuits available, SNTRJ avoids drawing clock power from your network switch. If running any cable to the clock location is impractical, SNRF avoids data cabling entirely — pair it with the ORNATE 2000 RFMS master. All of them can be monitored from our Management Server Software.