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Operation
minimum values. If an input value falls below the bottom of the
lowest range in auto-range mode, or below the bottom of a held
range, the display will begin to flash. Measurements can still be
made, but the input is outside of its specified range and accuracy
cannot be guaranteed. If the input falls to a value too low to actually
permit a measurement, the display will indicate "Input Low".
Hold Mode
When making measurements using any of the operating modes of
the 918B, you can "freeze" the values for all measured parameters
by simply pressing the "HOLD" button. You can then switch
between all of the different modes and determine their respective
values at the time "HOLD" was pressed. Pressing "HOLD" a second
time restores the instrument to normal operation.
Min / Max Readings
Recording of minimum and maximum values is suspended for any
period of time that the hold function is active. However, all
previously recorded values are retained. Refer to section 3.2 for
more information on minimum and maximum value recording.
2.11 Measurement of Phase Angle
The 918B is capable of measuring the phase angle, in degrees,
between the voltage input and the current input. The range for this
function is dependent on which phase convention has been selected
(refer to Section 2.2.1.2, "Changing the Phase Convention"). To
perform phase measurements with the 918B, both the voltage and
current inputs are used.
CAUTION
Do not exceed ±25 volts peak, with respect to earth
ground, on the (-) voltage input. The 918B is designed to operate
with the (-) input connected to earth ground or circuit neutral.