Knowledge is power essay

Introduction of Efficiency of Transformer Transformers form the most important link between supply systems and load. Transformer’s efficiency directly affects its performance and aging. The transformer’s efficiency, in general, is in the range of 95 – 99 %. For large power transformers with very low losses, the efficiency can be as high as 99.7%. The input and output measurements of a transformer are not done under loaded conditions as the wattmeter readings inevitably suffer errors of 1 – 2%. So for the purpose of efficiency calculations, OC and SC tests are used to calculate rated core and winding losses in the transformer. The core losses depend on the transformer rated voltage, and the copper losses depend on the currents through the transformer primary and secondary windings. Hence transformer efficiency is of prime importance to operate it under constant voltage and frequency conditions. The rise in the temperature of the transformer due to heat generated affects the life of ...

Canon will have a major mirrorless RF announcement  in a few days and it seems that Nikon is also planning a big announcement at the end of July ( July 21st? ). I am still not sure exactly what products will be announced later this month. The most likely scenario will be the  Nikon Z5  with  one, two, or three Z lenses . If the  Z6s and Z7s cameras  are announced, it will only be a development release. Here is an updated list of expected/rumored Nikon Z mirrorless cameras and lenses: New Nikkor Z lenses (new info added) Previously reported here Nikkor Z 24-50mm f/4-6.3 : this will probably be the new kit lens for the upcoming Nikon Z5 camera - it will be a small, light, compact (almost like a pancake), cheap plastic lens with a collapsible design similar to the  Nikkor Z DX 16-50mm . The new lens may even have a plastic bayonet (not sure). Nikkor Z 50mm f/1.2 S lens : a massive, solid lens with a lot of glass elements inside - similar in size to t...