Resistance/Continuity Measurement; Spark Plug Wires; Extension Cords; Appliance Cords - Calterm 66430 Manual Del Propietário

other test lead to the terminal on the circuit breaker
(see fig. 6). The tester should read 120 V AC.
Figure 6

7. Resistance/Continuity Measurement

For resistance and circuit continuity testing with power OFF:
1) Set the function/range switch to the appropriate ohms
setting. If basic circuit continuity tests are being made,
any of the ohms settings will do.
2) Touch the test leads to the resistor or non-energized
component to be measured. Use the 2000K range when
testing for resistance values in electronic components
such as resistors and potentiometers. If the value of
the component falls within the range of another setting,
reset the function/range switch to that setting for a more
accurate reading.
Common resistance and continuity measurements
Continuity tests are probably the most frequently performed
electrical troubleshooting procedures around the home.
Always remember that continuity checks are to be made with
the power to the circuit turned OFF. Polarity of the test leads is
not a factor in making continuity checks.

7.1 Spark Plug Wires

Always remove power to the circuit before using
WARNING
!
the multimeter in the ohms position to measure resistance or
check for continuity.
With the engine and ignition turned off, remove one spark plug
wire and visually inspect both terminal ends for corrosion;
inspect the wire's insulation for damage. Replace the spark
plug wire if corrosion or wear is visible. Set the function dial
on the meter to the 20K ohm setting. Contact one terminal
end with one tester probe and the other terminal end with the
other tester probe (see fig. 7). The polarity (direction of the
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leads) does not matter when checking continuity or measuring
resistance. Compare the reading to specifications in a service
manual for your vehicle. Good spark plug wires typically have
a resistance of ~ 3K ohms per foot, which may vary based on
=
the style of the plug wire. If the wire has an open (break in the
conductor) the meter will indicate a "1" on the left side of the
display. Make sure that you are contacting both terminals with
the tester probes before making your diagnosis. If the
resistance is beyond the specification in your service manual
the plug wire will need replacement. Check and replace each
plug wire one at a time to avoid mixing up the wires.
Figure 7

7.2 Extension Cords

Unplug the cord. Set the function/range switch to any of the
ohms settings. Touch one of the test leads to one of the metal
prong ends of the cord and insert the other lead in either one
of the receptacle slots on the other end of the cord, making
sure both leads are making good contact (see fig. 8). If the
display does not change, switch one of the test leads to the
opposite receptacle or prong, making sure of good contact.
If the display still does not change, the cord may need to
be replaced.

7.3 Appliance Cords

Unplug the appliance from its power source. Turn its power
switch to the ON position. Touch the test leads to the metal
prong ends of the cord. The tester should indicate a low
resistance value. If not, flex the cord while the leads are still in
contact with the metal prongs. If the display changes
erratically while the cord flexes, there may be a broken
conductor in the cord. If the display does not change at all
there may be an open circuit in the appliance. Should it be
determined that the cord is not the source of the problem, the
appliance may need to be disassembled in order to pinpoint
the problem. Refer to the owners manual of the appliance.
The manufacturer of the appliance may require that the
appliance be serviced only by a qualified repair technician.
Figure 8
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