User`s manual

The AC voltage function is specified as:
VOLTage:AC
and generally appears in the MEASure and CONFigure commands as:
MEAS:VOLT:AC? ... [(@channel_list)]
CONF:VOLT:AC ... [(@channel_list)]
Resistance
Measurements
The multimeter can measure resistance up to 1.048 MΩ. Measurement
resolution down to 60 µΩ is achieved with the appropriate range and
aperture or integration time settings. Measurements can be made using a
2-wire or 4-wire configuration.
How Resistance is
Measured
The multimeter measures resistance by turning on an internal current source
which induces a voltage across the unknown resistance. The induced
voltage is measured and is divided by the amount of current applied. The
result is the "measured" resistance (resistance = voltage/current).
Table 4-4 shows the amount of current applied to the unknown resistance
for a given range. Consider that the current flowing through the resistance
will cause a certain amount of self-heating, thus changing the resistance.
The effects of self-heating can be minimized by selecting a higher range
since less current is applied. However, measurement resolution is also
decreased.
Table 4-4. Current Source Values
Range Current
256 Ω
2048 Ω
16384 Ω
131072 Ω
1048576 Ω
488 mA
488 µA
61 µA
61 µA
7.6 µA
Two-Wire vs. Four-Wire
Measurements
The multimeter uses separate "sense" and "source" terminals when making
resistance measurements. The sense terminals measure (sense) the input
signal. The source terminals route current from the current source through
the unknown resistance. When the scanning multimeter makes a 2-wire
resistance measurement, the multiplexer connects these terminals together.
Thus, the input is sensed and the current is sourced through essentially the
same terminals. When the stand-alone multimeter is used, you must
connect the sense and source terminals to the resistance being measured.
This is a 4-wire configuration and the measurement must be specified
accordingly. Only 4-wire measurements can be made with the stand-alone
multimeter. Two-wire and 4-wire measurements can be made with the
scanning multimeter.
Chapter 4 Understanding the HP E1326B/E1411B Multimeter 87