Circle diagram constant air-gap induction motor images shown here, where, The circle diagram is drawn using the data obtained from no load and either short circuit or, in case of machines, blocked rotor tests by fitting a half-circle in points O and A. Beyond the error inherent in the constant air-gap assumption, the circle diagram introduces errors due to rotor reactance and rotor resistance variations caused by magnetic saturation and rotor frequency over the range from no-load to operating speed. Steinmetz equivalent circuit Circle diagram First conceived by A. Heyland in 1894 and B.A. Behrend in 1895, the circle diagram is the
A. A. M. Stols illustrated a number of his books. In 1951 Stols left for Latin America, where until 1962 he worked for UNESCO in Ecuador, Guatemala, and Mexico. After a brief stay in the Netherlands he returned to Mexico in 1963 where until his retirement in 1965 as a cultural and journalistic advisor. He then moved to Tarragona, Spain, where he died in 1973. A. A. M. Stols A. A. M. Stols (usually called Alexander or Sander, 1900-1973) was a Dutch printer and publisher, known best for his limited bibliophile editions of Dutch poetry. Stols was born in Maastricht, 28 January 1900. He