1 Product Overview

With the vigorous development of my country's national economy, the power load has increased dramatically, especially the continuous growth of impact and nonlinear load capacity of power electronic switching equipment, electrified railways, arc furnaces, etc., which has caused the power quality of the power system to deteriorate. The power quality problems such as waveform distortion, voltage fluctuation and flicker, and three-phase imbalance in the power grid are becoming more and more serious. As a result, transformer overheating, increased network loss, metering instrument errors, and communication interference will not only reduce the safety of the power supply and use equipment itself, but also seriously threaten the safety and economic operation of the power system. In order to protect the safe operation of the power system, all countries currently attach great importance to the management of power quality and have formulated relevant standards. my country has also successively promulgated national standards involving seven aspects of power quality, and relevant departments have also formulated corresponding "Power Quality Management Measures" - Appendix.

After a thorough investigation of power quality measurement and control, a careful analysis of the current status of similar products at home and abroad, and tracking the advanced level of international peers, our company has successfully developed a new generation of SC-GP-PQM power quality online monitoring device.

This device is a high-performance multifunctional power quality test and analysis instrument. It adopts DSP+ARM+CPLD core, 4.3-inch large-screen color LCD display, more compact structure and more powerful functions. It is suitable for 220KV, 110KV and 35KV substations, power plants and large electricity users.

2 Service Concept

Our company solemnly promises:

You buy not only the product, but also the meticulous and thoughtful technical support service ! ! ! ( =^_^= )

This product only needs ordinary workers to connect the power and install it on site! No debugging is required!

We provide free remote guidance, remote configuration and debugging services, and send data to the user's designated cloud platform.

Free IoT solution consulting services!

3 Product Features

3.1 Main Application

(1) Measurement and analysis of the quality of AC power supplied from the public power grid to the user end.

(2) Apply wavelet transform to measure and analyze the harmonics of non-stationary time-varying signals.

(3) Measure and analyze the power quality of the public power grid affected by various electrical equipment under different operating conditions.

(4) Regularly record and store changes in power parameters such as voltage, current, reactive power, frequency, and phase.

(5) Dynamic monitoring of power equipment to help users solve problems that arise during the adjustment and commissioning of power equipment.

(6) Test and analyze the causes of power system failures such as circuit breaker operation, transformer overheating, motor burnout, and automatic device malfunction.

(7) The characteristics of online, multi-parameter and high precision make the instrument widely used in power transmission and distribution, power electronics, motor drive and other fields.

3.2 Technical indicators of detection device

(1) Frequency measurement

Measuring range: 45～55Hz, center frequency 50Hz, measuring condition: signal fundamental component is not less than 80% FS

Measurement error: ≤0.01Hz

(4) The allowable error of fundamental voltage is ≤0.5%FS; the allowable error of fundamental current is ≤1%FS

(5) Measurement error of the phase difference between fundamental voltage and current: ≤0.5°

(6) Harmonic voltage content measurement error: ≤0.1%

(7) Harmonic current content measurement error: ≤0.2%

(8) Three-phase voltage unbalance error: ≤0.2%

(9) Three-phase current imbalance: ≤1%;

(10) Voltage deviation error: ≤0.2%

(11) Voltage variation error: ≤0.2%

(12) Power error: ≤0.5%

(13) Flicker error: ≤5%

3.3 Electrical Characteristics

Voltage and current accuracy level 0.1

Input characteristics: voltage range 400v

Current: 5A/1A

Working temperature: -25°— 50°

Frequency measurement range: 45HZ~55HZ

Hardware interface: RS485, Ethernet port, USB port, switch input (remote signal): DIC, DI1, DI2, etc.

3.4 Communication characteristics

Port 485: used for online communication with background software, with two communication protocols: 103 and modbus.

USB port: used to connect USB flash drive and statistical reports. (The device can save one year of historical records)

Switch input (remote signal): DIC, DI1, DI2.

Network port: used for online communication with background software, with modbus communication protocol.

3.5 Wiring Schematic

Three-phase four-wire system

Three-phase three-wire system

3.6  Wiring method 

(1) Three-component wiring (Y-connection, three-phase four-wire)

① Connect the Ua, Ub, Uc and N terminals of the instrument to the three-phase voltages A, B and C on the secondary side of the field voltage transformer and the neutral line N respectively.

② *Ia, *Ib, *Ic of the instrument are the current inputs; Ia, Ib, Ic are the current outputs.

(2) Two-component wiring (V-shaped connection, three-phase three-wire)

① Connect the Ua and Uc terminals of the instrument to the A and C voltages of the secondary side of the on-site voltage transformer respectively, connect the on-site B phase voltage to the rear terminal N of the instrument, and do not connect the Ub of the instrument.

② *Ia, *Ic of the instrument are the input terminals of current, Ia, Ic are the output terminals of current, and Ib is not connected.

(3) Relay contact connection

According to the configuration requirements, this instrument is equipped with 2 relay alarm contacts, with the contact capacity of AC 250V/8A or DC30V/8A. Each group of relay contacts is defined as: BJ1 line crossing alarm, BJ2 power failure alarm, BJCOM common terminal.

4 Core advantages of products

v The input adopts high voltage isolation and high-precision current transmitter, which greatly improves the anti-interference of the instrument and is safe and reliable to use.

v Chinese interface, key operation, easy to use

v Meet the national standard A- level instrument requirements, high precision

v Adopt DSP+ARM+CPLD core, fast processing speed and powerful software functions

v Multiple test parameters, grid harmonics, system frequency, voltage fundamental wave, deviation, etc.

v Large storage capacity, built-in 512M memory, single channel 5 minutes frequency can be saved for one year

v Can measure up to 3-phase voltage signal, 3-phase current signal

5 Communication Protocol

IEC103 protocol

Modbus protocol

Note: If you need to customize other communication protocols, please contact the business personnel.

6 Application Cases

7 Precautions

(1) Please connect and operate the instrument according to this instruction manual.

(2) Please enter the correct setting parameters before starting the test. The calibration calculations inside the instrument are dependent on the input setting parameters.

(3) The test menu item selection must be consistent with the actual test items and wiring.

(4) The measurement results can be stored continuously for up to 12 months. If the period exceeds 12 months, the earliest record will be overwritten. Please output it in time.

(5) If the instrument malfunctions, please contact our company immediately and do not start or disassemble it by yourself.

8 Contact Details

Website: www.daq-iot.com

Tel: +8619936624847

Email: shengrunan@daq-iot.com

9 appendix

Power Quality Management Measures

Ø GB /T 15945-2008 Power quality Permissible deviation of power system frequency

Ø GB 12325-2008 Power quality Supply voltage tolerance》

Ø GB /T 15543-2008 Power quality Three-phase voltage allowable unbalance degree》

Ø GB/T 30137-2013 Power Quality Voltage Sags and Short Interruptions》

Ø GB /T 14549-93 Power Quality Utility Grid Harmonics》

Ø GB 12326-2008 Power quality Voltage Fluctuation and Flicker》

Ø GB 24337-2009 Power Quality Public Grid Interharmonics 》