41
9
Electrical
Wiring
9.1
General
9.2
Power
Supply
Wiring
Power
supply
wiring
design
and
installation
should
adhere
to
the
following
requirements:
Separate
power
supplies
should
be
provided
for
the
indoor
units
and
outdoor
units.
Where
five
or
more
outdoor
units
are
installed,
additional
residual
current
protection
(leakage
protection)
should
be
installed
as
shown
in
Figure
3
‐
9.1.
All
the
indoor
units
in
a
system
(i.e.
all
the
indoor
units
connected
to
the
same
set
of
outdoor
units)
should
be
tied
into
the
same
power
circuit
with
the
same
power
supply,
overcurrent
and
residual
current
protection
(leakage
protection)
and
manual
switch,
as
shown
in
Figure
3
‐
9.2.
Do
not
install
separate
protectors
or
manual
switches
for
each
indoor
unit.
Powering
on
and
shutting
down
all
indoor
units
in
a
system
should
be
done
simultaneously.
The
reason
for
this
is
that
if
an
indoor
unit
that
is
running
were
to
suddenly
power
off
whilst
the
other
indoor
units
continued
running,
the
evaporator
of
the
powered
‐
off
unit
would
freeze
since
refrigerant
would
continue
flowing
to
that
unit
(its
expansion
valve
would
still
be
open)
but
its
fan
would
have
stopped.
The
indoor
units
that
remain
running
would
not
get
sufficient
refrigerant
so
their
performance
would
suffer.
Additionally,
liquid
refrigerant
returning
directly
to
the
compressor
from
the
powered
‐
off
unit
would
cause
liquid
hammering,
potentially
damaging
the
compressor.
For
outdoor
unit
power
wire
sizing
and
circuit
breaker
sizing,
refer
to
Table
2
‐
6.1
in
Technical
Manual,
6
“Electrical
Characteristics”.
Caution
All
installation
and
wiring
must
be
carried
out
by
competent
and
suitably
qualified,
certified
and
accredited
professionals
and
in
accordance
with
all
applicable
legislation.
Electrical
systems
should
be
grounded
in
accordance
with
all
applicable
legislation.
Overcurrent
circuit
breakers
and
residual
‐
current
circuit
breakers
(ground
fault
circuit
interrupters)
should
be
used
in
accordance
with
all
applicable
legislation.
Wiring
patterns
shown
in
this
data
book
are
general
connection
guides
only
and
are
not
intended
for,
or
to
include
all
details
for,
any
specific
installation.
The
refrigerant
piping,
power
wiring
and
communication
wiring
are
typically
run
in
parallel.
However
the
communication
wiring
should
not
be
bound
together
with
the
refrigerant
piping
or
power
wiring.
To
prevent
signal
interference,
the
power
wiring
and
communication
wiring
should
not
be
run
in
the
same
conduit.
If
the
power
supply
is
less
than
10A,
a
separation
of
at
least
300mm
between
power
wiring
and
communication
wiring
conduits
should
be
maintained;
if
the
power
supply
is
in
the
range
10A
to
50A
then
a
separation
of
at
least
500mm
should
be
maintained.
Notes
for
installers