WZDN-35C Portable Power Harmonic Tester

The ideal power system should provide users with a constant frequency sine waveform voltage. With the development of power electronics technology, direct current transmission and high-power single-phase rectification technology are widely used in industrial sectors and electrical equipment, such as high-power thyristor devices, switch power supplies, variable frequency speed regulation, etc. These typical nonlinear loads will suck or inject harmonic currents from the power grid, causing voltage distortion, pollution of the power grid waveform, deterioration of power supply quality, increased additional losses, and decreased transmission capacity, becoming important factors affecting power quality.

In the power grid, three-phase load imbalance, power system resonance grounding, etc. can generate negative sequence, and high-power rectification and nonlinear equipment can generate harmonics. Negative sequence and harmonic seriously affect the quality of power supply, and they first affect the safe operation of power equipment. Harmonics may cause resonance, and the high voltage of resonance is applied to both ends of the capacitor. Because high-order harmonics have a small impedance to the capacitor, the capacitor is prone to overload and breakdown; Higher harmonic current flows into the transformer, causing an increase in iron core loss; High harmonic current flowing into the motor not only increases the loss of the iron core, but also causes vibration of the rotor, seriously affecting the machining quality; High order harmonics cause protective equipment to malfunction, resulting in increased system losses; High order harmonics cause voltage resonance in the power system, leading to overvoltage on the lines and breakdown of equipment insulation. Negative sequence and harmonic waves not only have a thermal effect on the generator, generating local heat, but also cause vibration and noise in the generator set, seriously threatening the safe and stable operation of the unit.

The WZDN-35C portable power harmonic tester launched by our company is a high-performance multifunctional electrical energy testing and analysis instrument. Adopting DSP+ARM+CPLD core, the 5.5 "large screen color LCD (320 × 480 dot matrix) display makes the structure more compact, the functions more powerful, and the display more convenient. The power quality analyzer is a power quality monitoring device that combines high-speed sampling, calculation, analysis, statistics, communication, and display functions. Real time monitoring of power quality indicators such as harmonic content, total harmonic distortion, three-phase voltage imbalance, flicker, voltage deviation, voltage fluctuation, frequency, active power, reactive power, true power factor, phase shift power factor, true effective value, positive and negative sequence of up to 63 harmonics in the power grid. Backend management and analysis software, with rich functions and easy operation.

Electric harmonic tester, portable electric harmonic tester

1. Safe and reliable

The voltage input adopts a high-voltage isolation module (2000V, response time<2 μ S), and the current input adopts an alternating current clamp (0-50KHz, 0-5Arms) to safely isolate the input signal from the measurement system. This not only makes the power quality analyzer safe, reliable, and convenient to use, but also greatly improves its anti-interference ability.

2. Easy to use

Portable structure, small size, light weight, one person can carry the instrument to the site for testing; Equipped with a high-performance lithium battery, it can work continuously for ten hours without an external power source.

3. High precision

The data acquisition channel adopts a single channel single A/D design, with each channel having a dedicated 16 bit parallel A/D. All channels are fully synchronized for sampling, resulting in higher accuracy and faster speed. Moreover, any A/D damage in one channel does not affect the normal acquisition of data in other channels.

4. Strong software functionality

Adopting DSP+ARM+CPLD cores, the power quality analyzer has fast processing speed and rich software functions, making it suitable for complex testing and data processing work, greatly improving testing efficiency and level. The device panel is equipped with a large screen color display, which graphically displays real-time data of the main power quality monitoring indicators.

5. Communication interface

The tester provides a USB interface for data storage and communication with a computer for data transmission.

6. Real time printing

The power harmonic tester is equipped with a micro thermal printer that can print real-time test data on site at any time.

7. Multiple testing parameters

1) Basic measurement quantity

Grid frequency; Effective values of voltage and current; Total active power, reactive power, and power factor.

2) Basic monitoring indicators

a) Effective values of three-phase fundamental voltage and current, fundamental power, power factor, phase, etc;

b) Voltage deviation;

c) Frequency deviation;

d) Three phase voltage imbalance, three-phase current imbalance, negative sequence voltage, current;

e) Harmonics (2nd to 63rd order). Including the total harmonic distortion rate of voltage and current, the content, amplitude, and phase of each harmonic;The active and reactive power of each harmonic;

3) Advanced monitoring indicators

a) Interharmonics;

b) Voltage fluctuations and flicker;

c) Voltage surge, sudden drop, short-term interruption;

8. Large capacity storage

The USB interface stores data in minutes (with adjustable intervals) and allows for continuous historical data. At the same time, this machine can save basic monitoring indicators and advanced monitoring indicators in real-time on site, and the statistical time interval can be set (5-second-2-hour interval). The data can be saved on the device for a maximum of 1 year, and then updated according to the "first in, first out" principle. Local data can be exported to a USB drive.

9. GPS timing function (extended function)

The device has a GPS hard timing interface, which can accept IRIG-B code timing or second pulse timing signals and maintain consistency with the clock of the remote management center.

10. Backend management analysis software

The Power Quality Analyzer Pro Management Analysis Software is a dedicated backend management and analysis software that runs on the WIN9X/2000/XP/NT operating system. It has a user-friendly interface, graphical and curve analysis functions, and is equipped with relevant information queries, national standard queries, and other content. It has an online statistical function for the main monitoring indicators, which can calculate the maximum, minimum, average, and 95% probability high values of monitoring indicators within a time period.

1. Frequency measurement

Measurement range: 45-55Hz, center frequency 50Hz, measurement conditions: the fundamental component of the signal is not less than 80% F.S

Measurement error: ≤ 0.01Hz;

2. Input voltage range: 10V~450V (special range can be customized)

3. Input current range: 10A (other ranges can be selected according to user requirements)

4. Fundamental voltage and current amplitude: The allowable error of fundamental voltage is ≤ 0.2%; Allowable error of fundamental current ≤ 0.2%

5. Measurement error of phase difference between fundamental voltage and current: ≤ 0.5 °

6. Harmonic: meets the A-level requirements in GB/T 14549-1993;

7. Inter harmonic: meets the A-level requirements in GB/T 24337-2009;

8. Three phase voltage imbalance: ≤ 0.2%

9. Three phase current imbalance: 0.5%;

10. Voltage deviation error: ≤ 0.2%

11. Power and power factor: ≤ 0.5%

12. Flicker: 5%;

13. Voltage fluctuation: 5%.

14. Device interface (extended function): GPS hard time synchronization, IRIG-B code time synchronization, or second pulse time synchronization signal.

15. Working hours: The internal battery can work continuously for 10 hours

16. Dimensions (mm): 300 × 225 × 135 (length × width × height)

17. Weight: 1.5kg