ABB ABB-free home, System Manual

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03 Planning and Installation ABB-free@home
®
8
│ System Manual
Topology of line participants
The free@home system communicates via the data bus.
This means that each participant must be connected to
the bus to be able to communicate with other participants.
Participants
Each free@home device, with the exception of the power
supply, counts as participant. Up to 64 participants can be
connected to the bus.
Note:
The System Access Point also counts as a participant.
Line topology (Fig. 3)
The free@home bus line can be installed in almost any
manner desired.
» Mixing the line topologies of linear, star and tree is
permitted.
» Only rings must not be set up.
» No terminal resistors are required.
Lengths and distances of lines (Fig. 4)
» A - Max. lengths of lines: The lengths of lines within a
line are limited to a total length of max. 1,000 m.
» B - The maximum distance between power supply and
the last participant: max. 350 m.
» C - The maximum distance between two participants:
max. 700 m.
BUS line
The bus line leads to the participants.
» A KNX-certified bus line (J-Y(ST)Y 2x2x0.8) is to be
used.
» Aside from the necessary physical characteristics
(number of wires, cross-section, insulating voltage,
etc.) the bus line can be differentiated immediately
from other low-current lines.