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Operation
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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.
2.4 Measurement of AC Volts
The 918B Phase Angle Multimeter is capable of rms voltage
measurements of between 0.2 and 1000 volts, over a frequency
range of 45 to 500 hertz. Because an rms-to-dc converter is
employed, the value displayed will be the true rms value of the
voltage measured. For measurement of ac voltage, the current input
is not used.
CAUTION
Do not exceed ±25 volts peak, with respect to earth
ground on the (-) voltage in put. The 918B is designed to operate
with the (-) input connected to earth ground or circuit neutral.
Procedure
1.
Switch the unit into the ac voltage mode by pressing the key
labeled "Vrms".
2.
Plug the supplied test probes into the voltage input terminals,
with the red wire connected to the (+) terminal and the black
wire connected to the (-) terminal.
3.
Connect the black lead to the circuit neutral or ground, or the
point to be used as the reference for the measurement.