SECTION 2—INSTALLATION/SEQUENCE OF OPERATION
Part No 1164934
13
Perfecto
2
™
V
The
electrical
activation
of
the
4
‐
way
Valve
is
accomplished
every
8
to
15
seconds
by
the
pressure
sensor
and
P.C.
Board
electronics
when
the
pressure
reaches
a
set
point
of
21
p.s.i.
(144.79
kPa)
output
flows
4
L/min
and
above
or
16
p.s.i.
(110.32
kPa)
output
flows
3
L/min
and
below.
The
time
between
cycles
is
dependent
on
altitude,
flow
rate
and
internal
environmental
factors.
A
P.E.
valve
opens
just
prior
to
the
shift
of
the
4
‐
way
valve.
This
allows
highly
concentrated
oxygen
to
enter
the
just
exhausted
bed
from
the
top.
This
additional
pressure
allows
the
bed
to
start
its
cycle
at
a
higher
pressure.
The
P.E.
valve
will
close
just
after
the
shift
of
the
4
‐
way
valve.
If
main
power
is
lost,
the
Battery
Free
Power
Loss
Alarm
will
sound
a
short
ʺ
BEEP
ʺ
,
with
a
long
pause
after.
All
units
are
equipped
with
a
diagnostic
alarm
system
that
signals
if
the
pneumatic
pressure
or
electrical
systems
malfunction.
The
troubleshooting
guide
in
this
manual
explains
the
alarm
system
signals
and
reasons,
in
detail.
Refer
to
Troubleshooting
on
page 16.
SensO
2
Oxygen Sensor Technology - Ceramic Zirconia
Sensor
Technical Description
The
oxygen
being
produced
by
the
concentrator
flows
out
of
the
product
tank
and
into
the
flowmeter.
A
small
flow
of
oxygen
produced
by
the
unit
is
sent
through
a
precision
orifice
to
the
oxygen
sensor
mounted
on
the
printed
circuit
board.
As
the
oxygen
enters
the
sensor,
it
passes
through
a
screen
and
contacts
the
sensing
disk.
Electric
current
flowing
through
a
metal
film
resistor
heats
the
disk
in
excess
of
300°
C.
Oxygen
molecules
contact
the
electrode
of
the
disk
and
pick
‐
up
extra
electrons
to
become
oxygen
ions.
These
oxygen
ions
are
attracted
to
the
electrode
on
the
bottom
of
the
zirconia
sensing
disk.
Because
of
the
crystal
structure
of
the
zirconia,
only
oxygen
ions
can
pass
through.
When
the
oxygen
ions
reach
the
bottom
electrode,
the
extra
electrons
are
released
from
the
oxygen
ions
and
oxygen
molecules
return
to
the
air.
The
number
of
electrons
is
directly
related
to
the
oxygen
concentration.
The
electrons
travel
to
the
P.C.
board
where
they
are
counted
and
the
oxygen
concentration
reading
is
calculated.
A
microprocessor
on
the
P.C.
board
contains
software
that
interprets
the
signal
being
received
from
the
sensor.
It
compares
the
signal
to
clinically
acceptable
limits.
Signals
outside
of
the
clinically
acceptable
limits
generate
responses
in
the
form
of
lights,
audible
indicators,
and/or
system
shut
‐
down.
Operating Sequence
Once
the
power
switch
has
been
turned
on
(
)
,
the
SensO
2
circuit
will
wait
five
minutes
for
the
concentrator
to
begin
producing
clinically
acceptable
oxygen
and
the
oxygen
sensor
to
stabilize.
The
GREEN
light
will
illuminate
(indicating
normal
system
operation)
while
the
oxygen
sensor
is
warming
up.
I/
