Three phase harmonic online monitoring instrument

The main purpose of the three-phase harmonic online monitoring instrument is:Monitor the frequency, voltage quality, load current, harmonics, positive and negative sequence voltage, positive and negative sequence current, imbalance, reactive active power and other electrical quantities of substation busbars or low-voltage power grids around the clock, providing a basis for comprehensively grasping the quality of the power grid and carrying out power grid renovation and harmonic control.

Applicable occasions:

1. The secondary circuit of the 6-500 kV/50Hz high-voltage power grid is AC100V/50Hz.

2. 0.4 kV/50Hz low-voltage power grid.

Three phase harmonic online monitoring instrumentFeatures

The instrument measures and displays the following electrical energy parameters in real-time

1. Three phase voltage, current, grid frequency, and power factor.

2. The content of three-phase 3-31st harmonic voltage and harmonic current.

3. Total harmonic distortion rate of three-phase voltage and current.

4. Unbalance of three-phase voltage and current（ξ）

5. Positive sequence voltage, negative sequence voltage, positive sequence current, negative sequence current, and zero sequence current.

6. Three phase active power, reactive power, active kWh, and reactive kWh.

7. Running time

protective measures

1. Overvoltage, overcurrent protection, and lightning protection.

2. Power loss protection, data will not be lost within one year.

Statistical data:

1Voltage quality data includes

1.1 Total running time, qualified time, and qualified rate.

1.2 Exceeding the upper limit rate, exceeding the upper limit rate, exceeding the lower limit rate.

1.3 Maximum and minimum voltage values and their occurrence times.

2Harmonic monitoring data includes.

2.1 Total harmonic voltage content and distortion rate, 3-31st harmonic voltage components and content.

2.2 Total harmonic current content and distortion rate, 3-31st harmonic current components and content.

2.3 When harmonic voltage distortion is qualified, the qualification rate, the maximum value of distortion, and the time of occurrence.

2.4 When harmonic current distortion is qualified, the qualification rate, the maximum distortion value, and the time of occurrence.

measurement accuracy

1. Voltage measurement: Level 0.5.

2. Frequency deviation not exceeding 0.01Hz

3. Clock error: ≤± 1s per day, ≤± 5min per year

4. Maximum power consumption:<5VA

5. Harmonic measurement accuracy of power grid: Class B

Data Collection and Management

1. Equipped with RS232 and RS485 standard communication ports, it can be used for on-site data collection on PCs and handheld computers, or for data transmission through carrier waves, negative control, etc.

2. The instrument is equipped with a built-in MODEM. It can achieve timed and real-time summoning through the network.

3. The upper computer is based on the WINDOWS operating platform, and various collected data can automatically generate various reports, curves, and bar charts.

4. The report can be converted to WORD or EXCEL format for printing as needed. Various reports, curves, and bar charts can be sent externally.