These devices are supposed to indicate hottest spot in the winding based on the manufacturers heat run tests. At best, this device is only accurate at top nameplate rated load and then only if it is not out of calibration. They are not what their name implies and can be misleading. They are only winding …
Siemens to supply power engineering for transformer testing facility in Slovenia
Kolektor Etra (Energetski transformatorji d.o.o.), a Slovenian power transformer manufacturer, has given Siemens Industry Solutions an order to equip a transformer testing facility with new power engineering. The existing testing facilities in Ljubljana, Slovenia, will be expanded with a new transformer set with drive technology, a capacitor installation, the switchgear and control engineering. The new …
Risk and Consequences Of Transformer Fire
The risk of a catastrophic fire with a properly inspected, tested, and maintained transformer is small. Proper maintenance and thorough testing of the transformer will prevent or detect many events that could lead to explosion and/or fire. However, unforeseen events such as design defects, voltage surges, lightning strikes, structural damage, rapid unexpected deterioration of insulation, …
How To Connect Current Transformers?
The primary of a current transformer typically has only one turn. This is not really a turn or wrap around the core but just a conductor or bus going through the “window.” The primary never has more than a very few turns, while the secondary may have a great many turns, depending upon how much …
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. The designer has a certain choice of solutions which can be applied in order to …
What Are Partial Discharges On Cast Resin Transformers?
Partial discharges are electrical discharges occuring in insulating materials. The electrical discharge’s path only spans part of the insulating distance separating the conductors. The problem of partial discharges, whilst not existing in Low Voltage, is found in High and Very High Voltage. Partial discharges can occur in cavities within solid insulants, in gas bubbles in …
NEMA TP1 Energy Efficiency Standard
Single Phase and Three Phase 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 electricity received into usable output voltage. Since these transformers are …
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 oil cooled transformers, and the harmonised document HD538 for dry type transformers, which is still …
Parallel Operation Of Transformers
Most transformers installed in parallel have the same kVA, turn ratios, and impedances, which can make it difficult for power engineers in industrial and commercial facilities to understand circulating currents and load sharing. As systems change over time, and transformers are replaced or added, users need to know the impact of paralleling transformers using different …
Transformer Cooling Classes
Since no transformer is truly an “ideal” transformer, each will incur a certain amount of energy loss, mainly that which is converted to heat. Methods of removing this heat can depend on the application, the size of the unit, and the amount of heat that needs to be dissipated. The insulating medium inside a transformer, …
