
GASMAX CX Operation & Maintenance Manual, Revision 1.0
Page 27
CALIBRATION
PROCEDURE
Before
beginning
calibration,
make
sure
you
have
the
following
items:
A
cylinder
of
calibration
gas,
fixed
flow
regulator
and
an
appropriate
calibration
cup
connected
to
the
regulator
via
a
length
of
flexible
tubing.
If
necessary,
a
cylinder
of
‘zero
air’
may
be
necessary
if
the
absence
of
target
gas
cannot
be
confirmed.
GDS
Corp
recommends
a
flow
rate
of
0.5
liters
/
minute
for
standard
gases
and
a
flow
rate
of
1.0
liters
/
minute
for
highly
reactive
gases
such
as
chlorine
or
chlorine
dioxide.
To
calibrate
a
GASMAX
CX
detector:
1.
For
dual
channel
units,
press
the
NEXT
key
until
that
the
DATA
Display
screen
for
the
desired
channel
is
shown.
2.
To
enter
CAL
MODE,
press
the
DOWN
/
CAL
key
and
within
5
seconds
press
the
EDIT
key.
3.
The
screen
will
display
an
APPLY
ZERO
message.
Using
the
setup
shown
in
Fig.
5
‐
1,
apply
clean
ZERO
air
unless
it
can
be
guaranteed
that
no
target
gas
is
present.
After
the
reading
stabilizes,
press
the
EDIT
key
to
complete
the
ZERO
calibration.
4.
If
the
ZERO
CAL
SUCCESSFUL
message
is
displayed,
an
APPLY
SPAN
message
will
appear.
Apply
the
correct
SPAN
gas.
After
the
reading
is
stable,
(approximately
1
minute)
press
the
EDIT
key
to
Calibration
Cup
Fixed
Flow
Regulator
Cylinder
of
Calibration
Gas
Flexible
Tubing