Engine Tach (Rotation Speed) Testing "Rpmx10 - UNI-T UT106 Operating Manual

Model UT106: OPERATING MANUAL
J. Engine Tach (Rotation Speed) Testing "RPMx10"
(see figure 11)
Ignition Coil
The RPM means the rotating frequency of the main shaft
of the engine per minute.
1.
Set the rotary switch to RPMx10.
2.
As prompted at the LCD connect terminal, insert the red
test lead into the
COM terminal. Select an appropriate number of cylinders.
Connect the ends to be tested as illustrated.
l
If a DIS ignition system without any distributor board
is used in the automobile, connect the red test lead
probe to the TACH (tachometer) signal line (which
is connected to the computer DIS module of the
automotive engine). Refer to the automotive
servicing manual for the specific position.
If an ignition system with a distributor board is used
l
in the automobile, connect the red test lead probe
to the primary negative end of the ignition coil.
(Refer to the automotive servicing manual for the
specific position.)
3. Connect the black test lead probe to the good ground
terminal of the automobile.
4.
Upon the start of the engine or during its operation,
test the rotation speed of the engine and read the
displayed value from the display. The actual rotation
speed of the automobile to be tested should be equal
to the displayed value multiplied by 10. For example,
the actual rotation speed of the engine of the
automobile should be 2000 RPM (200 x 10) if the
displayed value is 200 and the meter is set at the
6CYL (6 cylinders) notch.
Red
Test Lead
Ground
Black
Test Lead
( figure 11)
terminal and the black one into the
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