5
IR270
‐
en
‐
GB_V1.0
12/17
Distance
to
Spot
Ratio
(Field
of
View)
The
meter’s
field
of
view
is
12:1
(distance
to
spot
ratio).
For
example,
if
the
meter
is
12
inches
from
the
target
(spot),
the
diameter
of
the
target
must
be
at
least
1
inch.
Refer
to
the
field
of
view
diagram
printed
on
the
meter
and
reproduced
here.
Measure
surfaces
from
a
maximum
distance
of
2
feet
whenever
possible.
The
meter
can
measure
from
further
distances
but
external
sources
of
light
may
interfere
with
the
readings
and
the
spot
size
may
be
so
large
that
it
encompasses
unintended
surface
areas.
It
is
necessary
to
ensure
that
the
size
of
the
target
is
larger
than
the
spot
size.
The
smaller
the
target,
the
closer
the
distance
should
be.
Measurement
Considerations
1.
The
object
under
test
should
be
larger
than
the
spot
(target)
size
(refer
to
the
field
of
view
section
above).
2.
Remove
frost,
oil,
grime,
etc.,
from
surface
before
taking
measurements.
3.
If
an
object's
surface
is
highly
reflective,
apply
masking
tape
or
flat
black
paint
to
the
surface
before
measuring.
4.
The
meter
may
not
make
accurate
measurements
through
transparent
surfaces
such
as
glass.
5.
Steam,
dust,
smoke,
etc.
can
obscure
measurements.
6.
The
meter
compensates
for
deviations
in
ambient
temperature
but
it
can
take
up
to
30
minutes
for
the
meter
to
adjust
to
wide
ambient
temperature
changes.
7.
To
find
a
hot
spot,
aim
the
meter
outside
the
area
of
interest
then
scan
(in
an
up
and
down
motion)
until
the
hot
spot
is
located.
Secondary
Display
Modes
The
secondary
display
area
is
located
on
the
bottom
of
the
meter’s
LCD.
You
can
step
through
the
secondary
display
modes
by
simply
short
pressing
the
MODE
(
M
)
button
from
a
powered
ON
or
powered
OFF
condition.
The
mode
icon
appears
on
the
lower
left
and
its
associated
value
appears
on
the
lower
right
(except
for
emissivity;
its
value
appears
on
the
upper
right).
Use
the
arrow
buttons
to
make
changes
to
a
setting
where
applicable.
Refer
to
the
sections,
below,
for
detailed
information
for
each
mode.
For
best
results,
pull
and
release
the
trigger
to
switch
the
meter
ON,
use
the
M
button
to
select
the
desired
mode,
and
then
pull
the
trigger
to
begin
measuring
with
the
desired
mode
now
active.
Maximum
Reading
(MAX)
Use
the
M
button
to
step
to
the
MAX
parameter,
then
pull
and
hold
the
trigger
to
start
scanning
surface
temperatures.
The
reading
on
the
lower
right
represents
the
highest
reading
recorded
during
the
current
measurement
scan.
When
pressing
M
from
a
powered
OFF
condition,
the
value
shown
on
the
lower
right
is
the
highest
reading
recorded
during
the
last
measurement
scan
performed.
