Cyclopedia of applied electricity : a general reference work on direct-current generators and motors, storage batteries, electrochemistry, welding, electric wiring, meters, electric lighting, electric railways, power stations, switchboards, power transmission, alternating-current machinery, telegraphy, etc. . ormer is fully loadedfive hours out of the day is not always a correct one. On many circuits from two to threehours of full load wouldbe more nearly the propervalue to use in calculatingthe all-day efficiency. If the efficiency of atransformer is low, it meansa direct loss of considerable
Cyclopedia of applied electricity : a general reference work on direct-current generators and motors, storage batteries, electrochemistry, welding, electric wiring, meters, electric lighting, electric railways, power stations, switchboards, power transmission, alternating-current machinery, telegraphy, etc. . ormer is fully loadedfive hours out of the day is not always a correct one. On many circuits from two to threehours of full load wouldbe more nearly the propervalue to use in calculatingthe all-day efficiency. If the efficiency of atransformer is low, it meansa direct loss of considerableenergy as well as greaterheating of the transformerand consequent deteriora-tion. If a transformer isto be used for lighting pur-poses, or is lightly loadedfor a large portion of thetime, a type which has a re-latively low core loss shouldbe selected so as to increasethe all-day efficiency. Iffully loaded all day, thelosses should be divided about equally between the copper and theiron losses. Regulation. By regulation of a transformer is meant thepercentage drop in the secondary voltage from no load to full loadwhen normal pressure is impressed on the primary. This drop isdue to the IR drop in the windings and to magnetic leakage. Inwell-designed transformers the loss due to magnetic leakage is about. Fig. 33. Transformer Connections from ThreePhase to Six-Phase for Rotary Converter 62 POWER TRANSMISSION 53 10 per cent, or less, of that due to the resistance drop. For non-inductive load (power factor= unity) the regulation is from 1 to 3per cent in good transformers. With induction load this is increasedto 4 or 5 per cent, or even more. Regulation should be considered carefully in selecting a trans-former for given service. Thus, if a transformer is to be used forlighting, its regulation should be of the best, since drop in voltagedue to the transformer is in addition to that due to the the same way the regulation of any system as a whole dependsto a certain exte
Size: 1359px × 1838px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthoramericantechnicalsoci, bookcentury1900, bookdecade1910
