Power Quality Analysis
The benefit of power quality testing:
Factories and enterprises can clearly see the effectiveness of power quality testing through:
• MAXIMUM TIME SAVINGS: The survey and testing are done without disconnecting equipment, reducing production downtime.
• PRODUCTIVITY INCREASE: Technicians can survey a wide area quickly. In particular, a safe distance is always set within the permissible range. Work done faster.
• PERFORMANCE IMPROVEMENT: Optimize and improve production problem. Risks are overcome before becoming major risks in the factory.
• REDUCE INVESTMENT COST: Finding and detecting early signs of machinery and equipment failures helps to reduce risks in the factory and increase the life of equipment in general. Technicians can anticipate equipment failures and plan replacement, reducing unwanted downtime.
Power quality testing is now widely used in the factory:
– Monitor and evaluate the system load
– Check the total harmonics and harmonic components (for example: 3rd harmonic is likely to cause current on the neutral wire, or burst capacitor ..)
– Know the source of the harmonic from the load or source
– Catch the incidents, the time occurs in a short time (range of milliseconds).
Retrieved source or load error (upstream- or downstream)
– Evaluate the losses and the energy saved when there is a change in the system compared to the previous one clearly by recorded and estiamted result by numbers based on the actual operating conditions of the equipments and the system, effectively serving the energy saving mission in the factory.
– Processing factories, manufacturing factories who need to follow Circular 39 Ministry of Industry and Trade
– Commercial buildings
– The manager of distribution electrical cabinets, engine systems.
– Managers want to improve the reliability of factory equipment and machines, minimize unexpected unplanned shutdowns.
– Energy audit department who need to assess energy consumption, loss energy and the efficiency of projects related to energy savings
Checking power quality according to Circular 39- The Ministry of Industry and Trade at the electrical connection points as well as checking the power quality at the transmission branches, each equipment using electricity in the plant is now considered a good solution.
Be effective in diagnostic maintenance based on the actual condition of the machine in service. From recorded results, it helps to improve the safety and reliability of equipments as well as the safety of the operator. Be proactively in maintenance by early detecting potential hazards that can cause major breakdown such as fire, equipment damage or unexpected shutdown during operation such as CB jump, capacitor explosion, or fire and equipment damage with unknown reasons.
Based on the survey and logging onsite, we can clearly see the power quality issues affecting the system in the order:
(1) Current capacity condition
(2) Harmonics in the system
(3) Ground / cable-winding
(4) Capacitor error
(5) Load problem
(6) Dip and Swell in systems
(7) Other problems
Figure 1: Statistics of equipment errors in the factory’s system
Measuring and monitoring power quality in accordance with Circular 39-BCT (sampling time: 10 minutes) and IEEE standards (short sampling time) to analyze power quality and troubleshoot electrical problems.
Step 1: Site inspection and equipment installation
– Site safety inspection and equipment installation
Step 2: Set up and logging the required data to be measured
– Set circuit type and electrical system parameters
– Check correct connection through voltage- current cursor
– Test the existence of current-voltage signal through the waveform and display value
– Set the parameters to be measured and the required time for the measurement
Step 3: Analyze the data obtained
(1) Check the system power quality according to Circular 39-BCT
(2) Check the actual factory load and breakdown
Step 4: Report analysis results and recommendations
(1) Show parameters and results of Pass / Fail status according to Circular 39-BCT for system power quality inspection
(2) Check loads, electrical status of rotating machine or evaluate energy saving solutions such as harmonic filters, installation of new inverters … and other plant requirements.
“The ‘Fluke 435-II (meets IEC61000-4-30 Class A standards) is suitable for indoor and outdoor operations, and is a reliable device used to test and troubleshoot power quality related problems.