Datasheet

 Trend

Available function keys:

Switch between voltage and current trends, the header shows parameters being

displayed.

Access to Events tables

Access to Cursor

Selection of Cursor move or Zoom

Switch between RUN and HOLD.

Event criteria such as threshold, hysteresis and others are preset, but they may be adjusted. The

adjustment menu is reached via the 【SETUP】 key and limits setup.

 Events tables

The Events table lists all threshold crossings of phase voltages. Thresholds according to international

standards or user –definable thresholds can be used. The Events table records major event

characteristics: start time, duration, voltage magnitude, event type, and occurrence phase etc.

 Tips and Hints

The occurrence of Dips and Swells may indicate a weak power distribution system. In such a system

voltage will change considerably when a big motor or a welding machine is witched on or off. This may

cause lights to flicker or even show visible dimming. It may cause reset and loss of data in computer

systems and process controllers.

By monitoring the voltage and current trend at the power service entrance, you can find out of the cause

of the voltage dip is inside or outside the building. The cause is inside the building (downstream) when

voltage drops while current rises; it is outside (upstream) when both voltage and current drop.

7.5. Harmonics

Harmonics measure and record harmonics and interharmonics up to the 50th. Related data such as DC

components, (THD) Total Harmonic Distortion, and K-factor are measured. Harmonics are periodic

distortions of voltage, current or power sinewave. A voltage or waveform can be considered as a

combination of various sinewaves with different frequencies and magnitudes. The contribution of each of

these components to the fundamental signal is measured. Readings can be given as a percentage of the

fundamental (%f), or as a percentage of full signal RMS (%r).Results may be viewed in a Bar Graph

display. Harmonics are often caused by non-linear loads such as DC power supplies in computers, TV’s

and adjustable speed motor drives. Harmonics can cause transformers, conductors, and motors to

overheat.

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