User`s guide

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PowerVisa Features

Touch screen

function

All PowerVisa functions described below are operable using a color LCD touch screen

technology. Users may use a finger and/or a PDA stylus to apply pressure to the LCD

screen to result in touch screen recognition. The touch screen display is also workable

with lineman gloves on. Touch screen buttons will appear in reverse-video to show

visual feedback of contact along with audible feedback. In order to reduce power

consumption, the backlight of the LCD screen times-out after a specified

programmable time of no user activity. The backlight reactivates by touching any part

of the screen.

Scope mode

Scope mode functions as an oscilloscope, displaying real-time waveforms of voltage

and current for up to eight channels simultaneously, with one second update rate. The

colors of waveform display are user programmable. Scope mode also provides a textual

display of rms values, division for axis values, and frequency.

Meter mode

Meter mode functions as a true rms voltmeter and a true rms clamp-on ammeter.

Voltage and current measurements, along with other calculated parameters, are

displayed on the Meter mode screens in both textual and graphical format.

Harmonics

Harmonics display the amplitude and phase of each harmonic to the 63rd harmonic in

both graphical and textual format.

Phasor diagram

The phasor screen displays a graph that indicates phase relations between voltage and

current based upon the angles at the fundamental frequency, as determined by Fourier

analysis. Phasor diagram displays voltage and current phasors for all channels.

Functioning as a phase angle meter, the unit can display system imbalance conditions

and provides such information in textual form also. The phase angle display can also

verify if monitoring connections have been made correctly. Animated phasor demo

rotations demonstrating resistive, inductive and capacitive loads can be displayed.

Flicker

Flicker is a phenomenon due primarily to rapid small fluctuations of the voltage. Loads

that exhibit continuous, rapid variations in the load current, particularly the reactive

component, can cause voltage variations often referred to as flicker. Flicker is

characterized by modulation at a frequency typically less than 25 Hz. Modulating

signal magnitudes as low as 0.5% of the fundamental for frequencies between 5-10 Hz

can result in perceptible light flicker.

Event

An event occurs when a programmed threshold limit is crossed. An event consists of

the pre-trigger cycle(s), trigger cycle(s), and post-trigger cycle(s).

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