Time systems & bells
Bodet exact-time systems for schools, hospitals, factories, offices and transport: one master clock synchronises every clock in the building over GPS, DHF radio or NTP. We complete the system with Harmonys and Melodys bells for announcements and signalling.
Types & options
The types in this category, under the names used in your written offer.
What a time system is
A time system starts from a master clock, which takes the exact time from a reference source and distributes it to every clock in the building. The slave clocks receive the time message, compare it with their own time base and correct themselves automatically; if the signal drops, they keep running independently on their own quartz time base until it returns.
The two decisions
Choosing a system comes down to two decisions: where the master clock gets the time, and how it passes it on.
- The reference source — radio synchronisation (the MSF, FI or DCF transmitters) or a GPS antenna, which takes the time and date from the network of 24 satellites. In both cases the winter/summer changeover is automatic.
- The distribution — wireless (DHF), coded AFNOR NF S 87 500 / IRIG B cable, 24 V pulses per minute, or an NTP network (Ethernet/PoE).
The distribution method is chosen according to the building: wireless DHF suits several buildings and the extension of an existing system, because it removes the cabling; coded cable distribution is used in large buildings such as airports and stations, and especially with digital clocks; pulse distribution remains the most economical solution for small systems.
Bells, announcements and clock ranges
The same system extends to bells and public address: the Harmonys range over an IP network and the Melodys range wireless broadcast scheduled signals, public announcements and emergency alerts. The exact time also reaches the Profil TGV analogue clocks and the digital clocks with an LED display (Style, World Style, HMT) or an LCD screen (Opalys).
Selected Projects
Frequently asked questions
How does the master clock get the exact time?
The master clock takes the time from a reference source: either by radio, from an MSF, FI or DCF transmitter, or through a GPS antenna, which receives the time and date from the network of 24 satellites. The time received is adapted to local time, with an automatic winter/summer changeover.
Wireless or cabled distribution?
Wireless (DHF) needs no cabling — the radio waves pass through walls over a radius of about 200 metres — and suits several buildings or the extension of an existing system. Coded cable distribution (AFNOR NF S 87 500 / IRIG B) is used in large buildings and with digital clocks, while 24 V pulse distribution remains the ideal and most economical solution for analogue clocks.
What happens if the signal is lost?
The slave clocks keep running on their own quartz time base until the signal returns. On a coded circuit, they run independently for one hour, then resynchronise automatically.
Can the same system also ring bells or make announcements?
Yes. The Harmonys (over an IP network) and Melodys (wireless, DHF) ranges broadcast scheduled signals, public announcements and emergency alerts. Paired with a Sigma master clock, Melodys marks the start and end of lessons or shifts, and a DHF relay controller can switch the connected bells on or off.
How many clocks can be connected to a system?
Up to about 100 clocks can be mounted on a coded cable circuit. An NTP network has no limit on their number: each clock is powered and synchronised over the Ethernet cable (PoE) or from an individual power supply.
What types of clocks can be integrated into the system?
The system integrates the Profil TGV analogue clocks, for indoor and outdoor use, and the digital clocks — the Style, World Style and HMT LED ranges, plus the Opalys LCD range. They all show the same time as the whole time system.
Have a project? Talk to an Oraexacta specialist.
Send us a few details or photos and we'll propose the technical solution that fits.