When Power Quality measurements are moving out of the control rooms there is a growing need for a state-of-the-art instrument which can handle tough demands from both the technical measurements and the environment.

Unilyzer 902 is a norm-compliant (IEC 61000-4-30, Class A) and 3rd party-certified field instrument, dust- and splash-proof (IP65), with a high performance that meets these demands.

Unilyzer 902’s options for remote communication, e.g. GSM modem, also helps you save time and money, since you can download the measure data and re-configure the unit from your office, without having to go to the location where it is installed.

Main functions

• Automatic transducer identification
• Measurements
• Quantities and units like V, A, W, VA, VAr, kWh, kVArh, PF, Cosj, Hz, IFL, PST, PLT.
• Transients >1 ms
• Voltage sags (dips) and swells
• Flicker
• Harmonics. Odd, even, interharmonics and directions.
• Current and voltage unbalance
• Signalling voltage
• K-factor for transformers
• All power quality parameters measured simultaneously
• Direction for power harmonics and disturbance

Performance

Unilyzer 902 uses DSP (Digital Signal Processor) for measuring all periods without time gaps. Together with the built-in hardware locking to the fundamental frequency this gives the highest possible accuracy. Four independent trig channels capture sags, swells, transients and interruptions.

Real-time measurement

Connected to a PC Unilyzer 902 provides access to an eight-channel oscilloscope, a harmonic spectrum analyser and a trend-graph. The most recent shows all measured parameters and events during the last twenty-four hours. All this without the need to download data to the host computer. The phasor diagram gives valuable information about phase relationships and instrument wiring.

Evaluation

• PQ Online for real-time presentation and evaluation.
• Possibility to export data and measured files to other software, for instance spreadsheets.
• PQ Secure is a system for power quality monitoring. Measured data, from among others Unilyzer 902, can be accumulated and transmitted to a main SQL database. More information about this software can be found under the headline “Monitoring equipment”.