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6.2 DHF clock
On leaving the factory, the DHF clock is set in “Initialisation” mode. After inserting the batteries,
the clock displays INIT for 5 seconds then 00:00.
The synchronisation search is limited to 4 hours. Beyond, the clock stops searching and
displays only 2 fixed dots. A press on one of the keys will restart the synchronisation search
for 4 hours.
It memorises the address of the transmitter and switches to normal mode automatically when
time is received.
In case of interference or absence of signal:
In DHF mode, if the synchronisation is not correct after 24 hours, the clock pictogram flashes
every 5 seconds and the display disappears with only the 2 dots fixed.
In DHFI mode, if the synchronisation is not correct after 24 hours, the clock keeps on
working on its own time basis with the 2 dots fixed.
If needed (change of communication channel, new installation…), the clock can be switched
to “Initialisation” mode in the technician menu.
6.3 24V parallel Minute or ½ minute 24V receiver
1. A time distribution network “Minute” or “½ minute” emit only impulses, so that it is necessary to
set the clock at the time of the this network.
To add a clock on a network, it is not necessary to stop this network. It is enough to set on
time and when it will received the next impulse from the master clock, it will add a minute.
For a 1/2 minute mode clock, if there is an offset of 30 seconds reverse the connection of the
line.
In fact, the same impulse is either positive or negative according to the connexion mode and
one of these two impulses emits per minute is the minute stroke (second zero).
The clock pictogram is displayed during 1/2 second, at each impulse.
Cristalys clock does not work with minute or ½ minute serial impulses.
6.4 DCF radio-synchronised clock
1. On the initial powering up, the time is initialised at 00h00mn00ss on 01/01/2000.
Radio reception is made on each clock setting in operation and each time the user sets the
time manually.
It is carried out automatically every night at 3am local time.
2. During the night, if reception is not correct after one hour, a new radio search is made the
following night at 3am.
If reception is not correct, the radio pictogram will flash every 5 seconds.
The radio clock is fitted with a double antenna enabling it to pick up the time no matter what
position the clock is in.
