PQM-707 is a portable, 3-phase Power Quality Analyser, providing its users with features for measuring, analysing and recording parameters of 50/60 Hz power networks and power quality in accordance with the European Standard EN 50160 and other standards. The analyser is class S, in accordance with the requirements of IEC 61000-4-30:2008.
Convenient operation is ensured by a 7-inch LCD with a resolution of 800×480 and a multi-point touch screen. It may be also operated using the attached stylus. The display provides the current view of the network parameters (including waveforms, vectors, tables). The user interface includes complete analyser configuration (selection of parameters for data recording/ and logging) and analysis of the recorded data (including time and harmonics diagrams and reports on compliance with standards).
Only two buttons are used to turn on the meter and start the data recording.
The analyser is equipped with five banana voltage terminals marked as L1, L2, L3, N and PE. The range of voltages measured by four measuring channels is max. ±1150 V. The use of external transducers enables the analyser to be used in networks with higher voltages.
Four terminals for current clamps allow user to connect several types of clamps to measure currents. The terminals may be connected to the following clamp types:
• flexible clamps [marked as F-1(A), F-2(A), F-3(A)] with nominal rating up to 3000A (differing from others only by coil diameter);
• CT clamps marked as C-4(A) (range up to 1000A AC), C-5(A) (up to 1000A AC/DC), C-6(A) (up to 10A AC) and C-7(A) (up to 100A AC).
Also for current, the nominal range may be changed by using additional transformers – for example using the transformer of 10 000 A / 5 A with clamps C-6 (A), the user can measure currents up to 10 000 A. The analyser automatically recognises the type of connected clamps.
The device has a user-accessible microSD memory card with a capacity of 4 GB. The card is used for storing recorded data files, reports and screenshots. The meter also has an internal memory with a smaller capacity, which is used for storing configuration files, standard settings.
Recorded parameters are divided into groups that may be independently turned on/off for recording purposes and this solution allows for efficient management of the space on the memory card. Parameters that are not recorded, leave more memory space for further measurements.
The meter is compatible with PC software Sonel Analysis , which also supports other analysers produced by Sonel. In the latest version, this software provides the current view of the measured network (“live” mode) and the analysis of recorded data.
The data may be read using the USB port (slot of B type to connect PC) or directly from a microSD card and inserting it to an external memory card reader. This software also allows export in a format suitable for Power Quality Health Check.
In addition, the analyser has a second USB port – type A, which may be used to connect an external memory stick. By using the interface of the analyser, the user may transfer selected files to the memory stick (such as files with reports and settings)
The analyser is powered from two sources: an external power supply adapter (input voltage 100…240 V AC, output 12 V DC) and from a removable Li-Ion battery pack. The fully charged battery pack provides at least 4 hours of uninterrupted operation without an external power supply. After connecting the power supply the battery pack starts to recharge. After the battery pack is discharged the meter stops its current operations (e.g. recording) and switches -off in the emergency mode. When the power supply from mains returns, the analyser resumes interrupted recording.
Additional options for recharging the meter is by connecting to a PC with USB cable or charger with USB output. The charging current is then reduced accordingly which means that charging time is longer. This type of charging works only when the analyser is completely switched off and not in sleep mode.
The analyser is designed to measure and record the following parameters:
• RMS voltages up to 760 VAC referred to PE input (measuring range up to ±1150 V),
• RMS currents: up to 3000 A (peak currents – up to ±10 kA at 50 Hz) using flexible clamps F-1(A), F-2(A), F-3(A); up to 1000 A (peak values – up to ±3600 A) using hard clamps C-4(A) or C-5(A); up to 10 A (peak values – up to ±36 A) using C-6(A) clamps, or up to 100 A (peak values – up to ±360 A) using C-7(A) clamps,
• crest factors for current and voltage,
• mains frequency within the range of 40..70 Hz,
• active, reactive and apparent power and energy, distortion power,
• harmonics of voltages and currents (up to 40th),
• Total Harmonic Distortion THDF for current and voltage,
• power factor PF, cosφ, tanφ,
• unbalance factors for three-phase mains and symmetrical components,
• flicker severity PST and PLT,
Some of the parameters are aggregated (averaged) according to the time selected by the user (available settings are 1s, 3s, 10s, 30s, 1min, 10min, 15min, 30min) and may be stored on a memory card. In addition to average value, it is also possible to record minimum and maximum values in individual averaging periods.
The analyser detects the following types of voltage events: dip, swell and interruption. The user may define two thresholds for current: exceeding (top value) of the maximum value and dropping below (bottom value) the minimum value. The current in the neutral channel has two independent thresholds. For DC systems, there are two thresholds: exceeding the maximum and minimum voltage value.
Event detection may be accompanied by recording the voltage and current waveforms and RMS values. These waveforms are recorded at the beginning and end of the event.