Electrical news and engineering . /^ or i/,times full load current, and the starting current in the line,on account of the transformer, is 82% of 4J4 times or full load current. The starting torcpie will be reduced to 82% on accountof the reduction of the motor current, and again to 82%> onaccount of the reduction of the magnetic field, since the. a\Ar\ t^p4. oV *^»^ Iig. 5—Induction Motor Stator strength of the magnetic lield is proportional to the vol!age, so the starting torque will be .h2 of .82 of 1^, or fullload torque. It will readily be seen that if the motor starts up liK
Electrical news and engineering . /^ or i/,times full load current, and the starting current in the line,on account of the transformer, is 82% of 4J4 times or full load current. The starting torcpie will be reduced to 82% on accountof the reduction of the motor current, and again to 82%> onaccount of the reduction of the magnetic field, since the. a\Ar\ t^p4. oV *^»^ Iig. 5—Induction Motor Stator strength of the magnetic lield is proportional to the vol!age, so the starting torque will be .h2 of .82 of 1^, or fullload torque. It will readily be seen that if the motor starts up , for example, where a fast and loose pulley is used, thestarting voltage can be still further reduced. Thus, if therequired starting torque is only :iO% of full load torcpie, thestarting voltage will be 45% of the line voltage; the start-ing current in the motor will be Z/z times full load current,and the starting current in the line times full Icjad c\ir-rent. It is possible in many ways to so modify the drive thatthe torque at starting is less than full load torque; thus, mention has already been made of the use of fast and loosepulleys. Friction clutches come under the same head. Air compressors are usually started up light by supply-ing the compressor with a bye-pass, which connects thetwo ends of the compressor together through a pipe
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Keywords: ., bo, bookcentury1800, bookdecade1890, bookidelectricalnewsen20donm
