Electric Motor
Calculation of shaded-pole motor losses and efficiency at full load in 6 steps
First, let’s say few words about shaded-pole motors, and then dive into calculation procedure. A shaded pole motor is the simplest form of a single phase motor and is very low in cost. It develops a rotating field by delaying… Read more
Jan 17, 2018 | By Edvard Csanyi
Electric Motor
Five factors that mess up motor efficiency and how to improve it
It must be emphasised that the standard electric motor is already a very efficient device with efficiencies above 80% over most of the working range, rising to over 90% at full load. However, because of the high energy consumption, and the… Read more
Dec 23, 2015 | By Edvard Csanyi
Electric Motor
Induction motor startup and losses calculation
The main objectives while starting an induction motor are: To handle high-starting current To achieve high-starting torque. As we know, rotor resistance determines starting torque. Usually, this rotor resistance is small, giving small starting torque, but good running conditions. So, the squirrel-cage motor… Read more
Mar 25, 2013 | By Edvard Csanyi
Testing and Commissioning
Transformer Routine Test – Measurement Of No-Load Loss And Current
The no-load losses are very much related to the operational performance of a transformer. As long as the transformer is operated, these losses occur. For this reason, no load losses are very important for operational economy. No-load losses are also… Read more
Feb 18, 2013 | By Edvard Csanyi
Transformers
Heating of the Dry-type Transformer
Although transformers can be classified by core construction (shell or core type), the more functional types of standardized classifications are based on how the transformer is designed for its specific application, and how the heat created by its losses is… Read more
Oct 15, 2012 | By Edvard Csanyi
Transformers
Transformer Extra Losses Due To Harmonics
Non-linear loads, such as power electronic devices, such as variable speed drives on motor systems, computers, UPS systems, TV sets and compact fluorescent lamps, cause harmonic currents on the network. Harmonic voltages are generated in the impedance of the network… Read more
Jun 22, 2012 | By Edvard Csanyi
Energy and Power
Difference between Power Transformer and Distribution Transformer
Power transformers are used in transmission network of higher voltages for step-up and step down application (400 kV, 200 kV, 110 kV, 66 kV, 33kV) and are generally rated above 200MVA. On the other hand, distribution transformers are used for… Read more
Aug 27, 2011 | By Jignesh Parmar
Electric Motor
Cooling and Ventilation of Electric Motors (IC)
All rotating electrical machines generate heat as a result of the electrical and mechanical losses inside the machine. Losses are high during starting or dynamic braking. Also, losses usually increase with increased loading. Cooling is necessary to continuously transfer the… Read more
Aug 08, 2011 | By Edvard Csanyi
Energy and Power
The Advantages Of Maintaining A High Power Factor
A high power factor eliminates penalty dollars imposed when operating with a low power factor. For many years, most utilities demanded a minimum of 85% power factor as an average for each monthly billing. Now many of these same utilities… Read more
Feb 03, 2011 | By Edvard Csanyi
Transformers
Price Of A Transformer
Today the production of transformers is characterised by a large variety of designs, manufactured in relatively short batches to meet the demands of a variety of customers with ever-changing expectations. Of course, fluctuations in commodity prices have a significant effect…. Read more
Jan 26, 2011 | By Edvard Csanyi
Energy Efficiency
NEMA TP1 Energy Efficiency Standard
Most commercial and industrial facilities require several low-voltage transformers to decrease the voltage received from the utility to the voltages used by various loads such as lighting, computers and other electrically operated equipment. Standard transformers convert approximately 95% of the… Read more
Jan 08, 2011 | By Edvard Csanyi
Transformers
Transformer Losses Standards
Unlike many countries around the world, Europe has no mandatory standard on energy efficiency of distribution transformers. The two main documents which describe losses in transformers are: the European Standard EN 50464-1, which has superseded the harmonised document HD428 for… Read more
Jan 07, 2011 | By Edvard Csanyi
