The dual measurement mode allows you to use the 2nd
display to show another item, thus viewing two different
measurement results at once.
When the multimeter is used in dual measurement mode,
both displays are updated from either a single
measurement or from two separate measurements. If the
primary and secondary measurement modes have the
same range, rate and rely on the same fundamental
measurement, then a single measurement is taken for
both displays; such as ACV and frequency/period
measurements. If the primary and secondary displays use
different measurement functions, ranges or rates, then
separate measurements will be taken for each display. For
example, ACV and DCV measurements.
Most of the basic measurement functions, except for
resistance/continuity/diode/capacitance can be used in
the dual measurement mode.