Why we should use power quality online monitoring device?

1. Introduction

The development of modern society cannot be separated from the support of electric energy, and the stability and quality of electric energy will greatly affect people's lives and work. Higher quality electric energy is very important for people's production and life. The online detection system of power grid electric energy can monitor the actual application of power grid electric energy in real time and record data during the application process. The technicians can analyze the data to judge the actual application of power grid electric energy, find out the equipment that is not operating normally and replace and repair it to ensure the quality of power grid electric energy. The detection indicators of the power grid power quality detection system are important standards for technicians to judge the power quality and the quality of power grid operation. The technicians can also judge whether the power quality of the power grid meets the actual requirements of my country for the power quality of the power grid by analyzing these indicators. At present, the indicators used in the process of power grid power quality detection include voltage deviation, frequency deviation, harmonics, voltage fluctuation, flicker, three-phase voltage imbalance, etc.

2. APView500 Power Quality Online Monitoring Device

The online power quality monitoring device is a device that monitors power quality indicators by analyzing and processing the introduced voltage and current signals. It is suitable for occasions that require accurate measurement of power quality indicator parameters, such as resolving power quality disputes agreed in the power supply contract, or verifying whether relevant power quality standards are met.

3. Functions

①Human-machine interface function

The device panel uses a 5-inch color LCD screen to display the real-time data of the main power quality monitoring indicators in a graphical manner. The device hardware clock can be set, and the monitoring parameters can be set and modified, and the device clock and password can be set.

②Record storage function:

The monitoring point data can be saved in real time. The 1-minute data (Max, Min, average, 95% probability maximum value, root mean square value) can be stored on the device for up to 90 days, and then updated according to the "first in, first out" principle.

③ Communication function

Two RS485 serial communication interfaces, supporting Modbus-RTU protocol, capable of reading all measured parameters; three Ethernet interfaces, supporting Modbus-TCP, IEC 61850 MMS, FTP, capable of reading all measured parameters; one Ethernet maintenance port for page and device software upgrades.

④GPS timing function

The device has a GPS hard timing interface and supports IRIG-B code timing.

⑤ Alarm function

The alarm function can be activated according to the limit values of various steady-state and transient power quality indicators set by the user. When an alarm is triggered, the device will record the event and trigger the recording.

⑥ Recording function

The device can trigger recording for each alarm event, and provides manual trigger recording, timed trigger recording and host computer trigger recording functions.

⑦ Local PQDIF file generation function

Statistical data is saved in PQDIF file format, and the recorded data includes fault recording waveforms and steady-state data within 2 hours. Steady-state data includes the data of "Max", "Min", "Average", "RMS value", and "95% probability value" that are counted by the device every 1 minute and maintained for 2 hours. The recorded fault recording data and steady-state data can be viewed through the tool software. Recording "Max", "Min", "Average", "RMS value", and "95% probability value" within 1 minute generates a recorded data point, and these data points form a storage file for 2 hours, and the line change trend can be observed by viewing the software.

⑧Web function

Integrated embedded Web Server function, supports login access by users with different permission levels. Different levels of users use different 8-digit passwords to log in, namely "Visitor": 00000000; "Administrator": ********; "Debugger": ********. Users can directly connect to the device through a browser to view power quality data and set device parameters in real time.