A master-slave clock system has one master clock that holds accurate time and any number of slave clocks that display the master's time. The master takes its time from GPS or from an NTP time server; the slaves follow the master. Every display in the facility shows the same time and is corrected automatically, so nobody has to walk around resetting clocks after a power cut.
Choosing the master clock
ORNATE 5000GDMS Series — a GPS digital clock with a built-in master function. It keeps GPS-precision time on its own display and drives additional slave clocks from the same GPS reference. Its remote GPS antenna can sit up to 25 metres away, so the clock body stays indoors while the antenna gets a clear view of the sky.
ORNATE 2000 RFMS — a LAN-based master clock that drives RF wireless slave clocks with no data cabling. The slaves need only a power connection, which can be daisy-chained from slave to slave, with a range of up to 25–30 m indoors and 50 m outdoors.
An NTP time server as the master — on sites with a network, a GPS NTP time server such as the ORNATE 7000 TSDRNT can be the time source for every networked slave clock and every computer on the LAN at once.
Choosing the slave clocks
The ORNATE 7500 Series covers three ways of connecting each slave clock: SNTPE over Power over Ethernet (one cable for power and time), SNTRJ over RJ45 with its own power supply, and SNRF over RF wireless from the master. All come in blue, red or green displays, HH:MM or HH:MM:SS format and 2 to 12 inch digit sizes. See digital slave clocks for a side-by-side comparison.
Where master-slave clock systems are used
Schools and colleges, hospitals, railway stations, airports, bus terminals, factories and office buildings — anywhere many clocks need to be visible and in agreement.
Monitoring the whole system
The ORNATE Management Server Software shows every master and slave clock on one dashboard, including RF and wired slaves with their role, site and live sync status.