43
0.75mm
2
three
‐
core
shielded
cable
should
be
used
for
communication
wiring.
Using
other
types
of
cable
can
lead
to
interference
and
malfunction.
Indoor
communication
wiring:
The
P
and
Q
communication
wires
should
be
connected
one
unit
after
another
in
a
daisy
chain
from
the
outdoor
unit
to
the
final
indoor
unit
as
shown
in
Figure
3
‐
9.4.
At
the
final
indoor
unit,
a
120
Ω
resistor
should
be
connected
between
the
P
and
Q
terminals.
After
the
final
indoor
unit,
the
communication
wiring
should
NOT
be
continued
back
to
the
outdoor
unit
–
that
is,
do
not
attempt
to
form
a
closed
loop.
The
P
and
Q
communication
wires
and
should
NOT
be
grounded.
The
shielding
nets
of
the
communication
wires
should
be
connected
together
and
grounded.
Grounding
can
be
achieved
by
connecting
to
the
metal
casing
adjacent
to
the
P
Q
E
terminals
of
the
outdoor
unit
electrical
control
box.
Outdoor
communication
wiring:
The
H1
and
H2
communication
wires
should
be
connected
one
unit
after
another
in
a
daisy
chain
from
the
master
outdoor
unit
to
the
final
slave
outdoor
unit
as
shown
in
Figure
3
‐
9.4.
Figure
3
‐
9.4:
Communication
wiring
configurations
–
correct
and
incorrect
examples
Master
unit
Slave
unit
Slave
unit
H1
H2
E
H1
H2
E
P
Q
E
P
Q
E
P
Q
E
P
Q
E
P
Q
E
Master
unit
Slave
unit
Slave
unit
P
Q
E
P
Q
E
H1
H2
E
H1
H2
E
P
Q
E
P
Q
E
P
Q
E
P
Q
E
