Figure 1-42.A parallax error on a meter with a mirrored scale.
MULTIMETER SAFETY PRECAUTIONS
As with other meters, the incorrect use of a multimeter could cause injury or damage. The following
safety precautions are the MINIMUM for using a multimeter.
Deenergize and discharge the circuit completely before connecting or disconnecting a
Never apply power to the circuit while measuring resistance with a multimeter.
Connect the multimeter in series with the circuit for current measurements, and in parallel for
Be certain the multimeter is switched to ac before attempting to measure ac circuits.
Observe proper dc polarity when measuring dc.
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.
Always start with the highest voltage or current range.
Select a final range that allows a reading near the middle of the scale.
Adjust the "0 ohms" reading after changing resistance ranges and before making a resistance
Be certain to read ac measurements on the ac scale of a multimeter.
Observe the general safety precautions for electrical and electronic devices.