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A52.
a. Use meggers for high-resistance measurement only.
b. Never touch the test leads when the handle is being cranked.
c. Deenergize and discharge the circuit completely before connecting a megger.
d. Disconnect the item being checked from other circuitry, if possible, before using a megger.
A53. A single measuring device capable of performing the functions of a dc voltmeter and ammeter, an
ac voltmeter and ammeter, and an ohmmeter.
A54. It is much more convenient to have one meter with several functions than several meters each with
a single function.
A55. By changing the position of the function switch.
A56. The meter movement reacts to average ac voltage and current and the effective value is desired.
A57. To stop parallax error
A58. Make sure no image of the pointer is visible in the mirror when reading the meter.
A59.
a.
Deenergize and discharge the circuit completely before connecting or disconnecting a
multimeter.
b.
Never apply power to the circuit while measuring resistance with a multimeter.
c.
Connect the multimeter in series with the circuit for current measurements, and in parallel for
voltage measurements.
d.
Be certain the multimeter is switched to ac before attempting to measure ac circuits.
e.
Observe proper dc polarity when measuring dc.
f.
When you are finished with a multimeter, switch it to the OFF position, if available. If there is
no OFF position, switch the multimeter to the highest ac voltage position.
g.
Always start with the highest voltage or current range.
h.
Select a final range that allows a reading near the middle of the scale.
i.
Adjust the "O ohms" reading after changing resistance ranges and before making a resistance
measurement.
j.
Be certain to read ac measurements on the ac scale of a multimeter.
k.
Observe the general safety precautions for electrical and electronic devices.
A60. To measure current safely and easily (with no need to disconnect the wiring of the circuit).
A61. Power.
