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A40.
a. Always connect a voltmeter in parallel.
b. Always start with the highest range.
c. Deenergize and discharge the circuit before connecting or disconnecting the voltmeter.
d. In a dc voltmeter, observe the proper polarity.
e. Never use a dc voltmeter to measure ac voltage.
f.
Observe the general safety precautions of electric and electronic devices.
A41. Resistance.
A42. Circuit continuity.
A43. The ohmmeter is connected in series with the resistance to be measured.
A44. An ohmmeter has several internal range resistors and a switch or a series of jacks to select the
proper range.
A45. The middle of the scale.
A46. Series and shunt.
A47. Series ohmmeters have 0 on the right end of the scale and on the left end of the scale. Shunt
ohmmeters are the opposite.
A48.
a. Deenergize and discharge the circuit before connecting an ohmmeter.
b. Do not apply power to a circuit while measuring resistance.
c. Switch ohmmeters to the OFF position, if provided, or to highest range and remove meter
leads from the meter when finished measuring resistance.
d. Adjust the ohmmeter after changing resistance range and before measuring reading indicates
the resistance.
A49. To measure high resistance.
A50. Connect one lead to the insulation and one lead to the conductor. Turn the handcrank until it starts
to slip. Note the reading.
A51. Infinity.
