Power Quality Monitoring Device

The power quality online monitoring device, as a detection product, is suitable for power plants, substations, wind farms, PV power stations, and power supply systems of large factories and mines in the petroleum, coal, iron and steel, metallurgy and chemical industries with the voltage from 380V to 220kV. By monitoring the power quality of critical points in the power system, the device can keep track of the power quality condition for a long duration and help with power quality problem analysis.

Product Overview

PRS-7177 power quality online monitoring device is an intelligent data acquisition and processing terminal specially developed for solving problems related to power quality. It can continuously monitor power quality data around the clock. Developed based on an IEC61850 model, PRS-7177 power quality online monitoring device has flexible and extensible standard communication interfaces and fully open digital interfaces. It can be flexibly applied to smart or conventional substations.

CYG ET provides various models of power quality online monitoring devices: such as analog (half-layered, multi-interval) and digital models. They can be used to cater for power quality monitoring requirements in different scenarios.


Product advantages

  • Steady state monitoring

    Fundamental voltage and current, active power, reactive power, apparent power, power factor, frequency deviation, voltage deviation, 2-50 harmonic waves, 0.5-49.5 inter harmonic waves, voltage fluctuation, short-term flicker, long-term flicker, three-phase imbalance and sequence component
  • Transient state monitoring

    Waveform data of voltage swells and sags, short interrupts, and action triggering
  • Storage

    The device has the function of local storage of power quality data. According to the set storage interval, steady-state data are analyzed in the form of PQDIF file and saved as historical data; In addition, the device can generate log files of steady state, transient state, teleindication and other types, and the file storage duration is at least 3 months.
  • Wave recording

    The device can record the voltage or current waveforms when power quality transient events occur in the system. It records the real-time data before and after an event, and save an event log for inquiry
  • Security authority

    The device complies with the Regulations on Safety Protection of Power Monitoring Systems to ensure information security. It has different operation authority, and the corresponding operation is allowed only after the user name and password are verified
  • Remarkable communication capability

    The device provides a variety of communication interfaces. It enables communication with a remote power quality monitoring and management center through the industrial Ethernet interface, and allows local communicate through the RS485 interface.

Technical parameters

Performance indexes are as follows:

Fundamental voltage and current error

≤ ±0.1%

Voltage deviation and error

≤ ±0.1%

Frequency deviation and error

≤±0.002Hz

Harmonic waves

Three-phase voltage imbalance

≤±0.15%

Three-phase current imbalance

≤±0.5%

Flicker error

≤ ±5%

Voltage fluctuation error

≤ ±5%

Power measurement accuracy

≤ ±0.5%

Power factor

≤ ±0.5%

Voltage transient state

≤ ±0.2%Un