Portable power quality instrument built on a third-generation measurement platform

Metrum PQX3-SPQ is developed on Metrum’s latest instrument platform and meets the highest accuracy class, Class A. It can therefore be used as a reference instrument in power quality-related cases.

The instrument is user-friendly and compact enough to be installed directly at points of delivery, facade-mounted meter cabinets, and industrial substations. It is easily mounted using built-in magnets.

Metrum PQX3-SPQ continuously generates power quality reports in accordance with EIFS 2023:3 for straightforward evaluation of measurement results. These reports can be used as documentation in power quality cases and disputes.

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High measurement performance enables new opportunities

The instrument’s high performance enables continuous waveform recording, which can be used in measurement applications requiring high-resolution data. The instrument also features a button that allows manual triggering of events.

The high measurement performance, with a sampling frequency of 51.2 kHz, expands the ability to detect fast events and disturbances in the power grid. It also improves the capability to measure harmonics in higher frequency bands, up to 9 kHz.

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Metrum PQX3-SPQ can be connected to Metrum’s database system to easily compare measurement data from other points in the power grid. This provides a better understanding of where different phenomena occur within the grid.
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Via the associated configuration interface, PQX3 Controller, extensive possibilities for real-time analysis are provided.

Technical specifications

Inputs/outputs

Parameters Specification Information PQX3-SPQ
Voltage inputs 0-460 V RMS Differential voltage inputs (+/-), 51.2 kHz/channel 4
HV Voltage inputs 0-6 kV peak Built-in high-frequency inputs (1 MHz) 4
Current inputs BNC, current clamps, ±3V Vrms Differential current inputs (+/-), 51.2 kHz/channel 4

Supply voltage

Parameters Specification Information PQX3-SPQ
Nominal supply 85-264 VAC/110-350 VDC (47-63 Hz) Yes
Internal backup 10 seconds Yes
Power supply of current clamps 5V USB, Type C For Rogowski current clamps 1
5V USB, Type A For Rogowski current clamps 1

Standards compliance

Parameters Specification Information PQX3-SPQ
IEC 62586 PQI-A-PI-H Product standard Yes
IEC 61000-4-30, class A, edition 3 < 0,1 % Reference instrument Yes
IEC 61000-4-7 Harmonic measurement Yes
IEC 61000-4-15 Flicker measurement Yes
EN 50 160 Calculated internally Yes
EIFS 2023:3 Calculated internally Yes
National standards (FoL, DEFU, NL, ZS387, etc.) Large number of standards supported Yes
Customised reports Calculated internally Yes
Storage interval Selectable storage intervals Yes
PQDIF format Selectable export Yes

Instrument

Parameters Information PQX3-SPQ
Memory 64 GB
Sampling frequency, U/I standard inputs 51,2 kHz
Sampling frequency, HF inputs 1 MHz
Accuracy IEC 61000-4-30, class A < 0,1 %
Resolution (U/I) Voltage/current inputs 16 bits
Resolution (GI) General measurement inputs 16 bits
Input impedance – voltage inputs 0.01 Ohm
Input impedance – current inputs 2,5 MOhm
Anti-aliasing filter Yes
PLL synchronisation Yes

Communication

Parameters Specification Information PQX3-SPQ
USB-C (Computer) Computer port, connect to configure Yes
USB-A Possibility to connect USB drive Yes
Ethernet RJ45 Yes
Support for external communication protocols IEC 61 850, IEC 62541, OPC-UA, Modbus-TCP, DDS/RTPS Yes
Time synchronisation For external time synchronisation NTP/PTP Yes