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FUNCTION REFERENCE

VOLT MEASUREMENTS

Description:

Voltage measurements can be made using the cursors or using automated, calculated measurement routines. Cursors operate in the analog mode as well as in the digital mode.

Calculated volt measurements are available in the digital mode only. Using the cursors, three voltage readouts can be selected:

-ΔV gives the voltage difference between the cursors.

-V1&V2 gives the absolute voltage with respect to ground for each cursor.

-ΔV-ratio gives a percentage that can be reset by using the ΔV=100% softkey. For more details refer to the section CURSOR READOUT.

In the digital mode, the MEASURE menu provides automatic voltage measurements.

This menu is reached via the key sequence ‘MEASURE >> MEAS 1(2) >> volt’. The TRACK control is used to select the type of measurement, and the Δ control is used to select the waveform.

The result of the measurement is displayed in the top left corner of the screen.

PRESHOOT OVERSHOOT MAX

HIGH

RMS

The following measurements are possible:

DC

PKPK

(Refer to section MEASURE MENU for details of signal parameters).

LOW

MIN

UNDERSHOOT

ST6670

-dc (DC VOLTAGE)

Measures the absolute dc level, related to the ground level of the signal. This is the average voltage of all samples in one period. If no full period is present, all input samples in the signal are included in the calculation.

 

1

dc =

k----------j--+----1--- × S(n)

where:

j = 1st mesial crossing [first sample if no full period]

 

k = 3rd mesial crossing [last sample if no full period]

 

S(n) = nth sample (j<=n<=k)

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Fluke PM3370B user manual Volt Measurements, Sn = nth sample j=n=k