Extech
Instruments
24 GX900-EU-EN V1.6 4/14
RPM
MEASUREMENTS
1.
Set
the
rotary
function
switch
to
the
RPM
position.
2.
Insert
the
black
lead
banana
plug
into
the
negative
COM
jack
and
the
red
test
lead
banana
plug
into
the
positive
V
jack.
3.
Touch
the
test
probe
tips
to
the
circuit
under
test.
4.
Read
the
RPM
value
on
the
display.
COUNTER
MEASUREMENTS
1.
Set
the
rotary
function
switch
to
the
RPM
position.
2.
Press
the
F1
key
(MENU),
move
the
menu
selector
to
the
item
labeled
COUNTER,
and
then
press
the
OK
key
3.
Move
the
menu
selector
to
the
item
labeled
START
and
press
the
OK
key
4.
Insert
the
black
test
lead
into
the
negative
COM
jack
and
the
red
test
lead
into
the
positive
V
jack.
5.
Touch
the
test
probe
tips
to
the
circuit
under
test.
6.
Read
the
Period
value
on
the
display.
7.
To
set
the
Count
Threshold
press
the
F1
key
(MENU),
move
the
menu
selector
to
the
item
labeled
COUNTER,
and
press
the
OK
key
8.
Move
the
menu
selector
to
the
menu
item
labeled
THRESHOLD
and
press
the
OK
key
9.
Enter
1
or
2
or
3
using
the
arrow
keys
and
then
press
the
F1
key
to
save.
Press
the
F1
key
to
return
to
the
measure
screen.