EXTECH
INSTRUMENTS
4
IR255
‐
en
‐
EU_V1.4
9/14
Operation
Meter
Power
The
meter
is
powered
by
one
9V
battery.
With
a
fresh
battery
installed,
the
meter
switches
ON
when
the
trigger
is
pulled.
The
battery
is
located
in
the
meter
handle;
pull
the
battery
compartment
lid
away
from
the
body
of
the
meter
to
open.
Refer
to
the
Maintenance
section
for
more
Battery
Installation
instructions.
The
battery
icon
provides
battery
status
indication.
Replace
the
9V
battery
as
soon
as
the
battery
status
icon
flashes.
Surface
Temperature
Measurements
1.
Hold
the
meter
by
its
Handle
Grip
and
point
it
toward
the
surface
to
be
measured.
Read
the
Field
of
View
section
below
for
distance
to
target
(spot)
ratio
information.
2.
Pull
and
hold
the
Trigger
to
turn
the
meter
on
and
begin
testing
in
Scan
mode.
The
display
will
light
if
the
9V
battery
is
good.
Replace
the
battery
if
the
display
does
not
light.
3.
While
continuing
to
pull
the
Trigger:
a.
Push
the
button
to
switch
the
laser
pointer
ON.
When
the
laser
is
ON,
the
laser
icon
will
appear
on
the
LCD.
Aim
the
red
laser
beam
approximately
a
half
inch
below
the
point
of
test
(pressing
the
Laser
button
again
turns
the
laser
off).
b.
Select
the
temperature
units
(
o
C
/
o
F)
in
the
Settings
Mode
(see
later
section).
c.
Push
the
button
to
switch
ON
the
LCD
backlighting
function.
4.
Release
the
Trigger;
the
reading
will
hold
for
approximately
9
seconds,
after
which
the
meter
will
automatically
shut
off.
5.
The
meter
defaults
to
the
programmed
conditions
in
use
when
the
meter
was
last
switched
OFF.
For
example,
if
the
laser
is
set
to
ON
and
the
temperature
units
are
set
to
o
F
at
the
time
the
unit
is
switched
OFF,
the
unit
will
switch
ON
and
use
the
same
settings.
Over
‐
range
Indicators
(OL
and
‐
OL)
If
the
temperature
measurement
exceeds
400°C
(752°F),
the
thermometer
will
display
OL
in
place
of
a
temperature
reading.
If
the
temperature
measurement
is
below
‐
20°C
(
‐
4°F),
the
thermometer
will
display
‐
OL
in
place
of
a
temperature
reading.
MAX
‐
MIN
Mode
Press
the
MAX
‐
MIN
button
to
view
the
maximum
temperature
reading
(MAX),
press
again
to
view
the
lowest
reading
(MIN).
Press
again
to
switch
the
MAX
‐
MIN
mode
off.
Display
Backlight
Press
the
backlight
button
to
switch
the
backlight
ON.
The
backlight
will
switch
OFF
automatically
after
several
seconds
to
conserve
battery
power.
