Traditional pulse systems
A traditional centralized clock system uses a specific device called master clock to send electrical impulses to receiver clocks which are equipped with a step movement. With each received impulse, the clock motor advances a step, which usually coincides with a minute; the clock movement is therefore generated by a step motor that in analog clocks moves a hand or turns a flap.
It is a simple system, connected using an open architecture with only two wires which allows for low-cost movements. This system was popular well before clocks with microprocessors arrived and is today normally used when expanding pre-existing systems, and is recommended for new installations when using analog clocks.
Innovative systems with NTP
Through the evolution of technology, clock system synchronization is based on Ethernet/LAN connectivity: the master clock (time server) provides information regarding the time which is necessary for synchronizing, and does this by using the NTP protocol based on the TCP/IP suite. The system is capable of synchronizing, configuring and monitoring the functions of all clocks connected to the network. Thanks to Power over Ethernet (PoE) technology, which makes it possible to power clocks by means of the ethernet infrastructure, the clock system is easily integrated within the company’s existing network infrastructure: this solution is recommended for all new installations.
Indipendent with GPS
In a noncentralized clock system, it is possible to have clocks controlled by an internal reference system, or also through the use of a public service by means of a GPS receiver. With this solution, clocks don't need to be connected to a master clock and they can therefore be adopted within urban installations, such as City Hall clocks, advertisement clocks, in any environment where an ethernet infrastructure is not available.