This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1901 edition. Excerpt: ...is the mechanical power developed by it divided by the electrical power supplied to it; that is, Efficiency of dynamo = Electrical power Mechanical power' Efficiency of motor = Mechanical power Electrical power These are the actual or commercial efficiencies of these machines, and should be about 90 ...
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This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1901 edition. Excerpt: ...is the mechanical power developed by it divided by the electrical power supplied to it; that is, Efficiency of dynamo = Electrical power Mechanical power' Efficiency of motor = Mechanical power Electrical power These are the actual or commercial efficiencies of these machines, and should be about 90 per cent in machines of i0 H. P. and over. The so-called "electrical efficiency " is misleading and of little practical importance, and should not be considered in commercial work. The mechanical and electrical power in the above equations are determined as described in the last section. Amperes Required To Give Different Powers, On The Various Constant-potential Circuits, Allowing For The Efficiency Of The Ordinary Motor. It is usually more convenient to test the efficiency of a dynamo by testing it as a motor with a Prony brake. But the efficiency of a dynamo may be determined very nicely by driving it with a calibrated electric motor, that is, one in which the power developed for any given number of volts and amperes consumed is known (section i4). Then it is only necessary to measure the watts generated by the dynamo when the motor is running at a certain power, and the efficiency of the dynamo is the watts divided by the known power. Another method is to employ two identical machines, one used as a motor driving the other as a dynamo. The shafts of the two machines should be directly connected by some form of coupling; a belt may be used, but its friction would cause a small loss. The watts generated by the dynamo divided by the watts consumed by the motor is the combined efficiency of the two machines, and the efficiency of each is the square root of that fraction. For example, if the combined efficiency is.8i, then that of...
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Add this copy of The Practical Management of Dynamos and Motors to cart. $15.42, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
Add this copy of The Practical Management of Dynamos and Motors to cart. $26.58, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
Add this copy of Practical Management of Dynamos and Motors (First to cart. $44.77, fair condition, Sold by Solomon's Mine Books rated 4.0 out of 5 stars, ships from Howard, PA, UNITED STATES, published 1894 by D. Van Nostrand Company.
