AERMEC GLLI20N Handbuch Seite 38

TTL NETWORK MANAGEMENT
No Master-Slave communication: the
slave fan coil cyclically await the zone
settings from the master fan coil. If for
some reason a slave fails to communi-
cate with the master, it switches OFF (i.e.
shutdown of all loads) after 10" from the
last command successfully received.
No Master-User Interface commu-
nication: if at some point the master
no longer communicates with the user
interface, it switches OFF after 10" from
the last command received from it. The
master will also send the OFF command
to all the slaves. The user interface also
gives the visual alarm AL 1
TTL NETWORK CONSTRAINTS
The constraint concerns the management
of the adjustment dead band; this should
be set on the master fan coil being that it
is ignored on the slaves because both the
setpoint and the operating season of these
depend on the master.
TTL NETWORK EMERGENCY FUNCTION
Master without Ambient Probe
The operating principle of the master
thermostat in the event that it functions
without ambient probe (or fault of its
local probe) follows what described in
the next paragraph.
T T L N E T W O R K A N T I - F R E E Z E
PROTECTION
Master: As described in the ANTI-FREEZE
PROTECTION paragraph, the thermostat
foresees as standard the control of the
ambient temperature to prevent this fall
to freezing values. If the master has to
operate in this condition, it will impose
all slaves to operate in AUTO mode with
setpoint at 12° C, even though these are
operating according to normal condi-
tions.
Slave without Ambient Probe
The Slave thermostat cards enter into
emergency mode not only if the local
probe is faulty but also if the master one
is faulty too. According to what previ-
ously mentioned, if the slave probe is
faulty and the master probe is working
properly, the slaves continue to operate
using that one of the master. If the slaves
begin to work in emergency mode, they
will be operated at the speed selected
in the user interface and the valve Y1 is
opened (this applies for both 2-pipe and
4-pipe system). Furthermore, the slaves
in emergency mode do not follow the
logic of the ON-OFF cycles based on the
position of the temperature selector but
are always in the ON phase, therefore
with ventilation always running.
Slave: Whereas if it is one of the slaves
operating according to the anti-freeze
protection (despite the master is oper-
ating in normal mode), it will oper-
ate in AUTO mode with setpoint at
12° C. This is the only case in which the
slave operates according to settings dif-
ferent to those dictated by the master.
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