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Title: |
1909 Article-Northern Electrical Mfg. Co., Steel Crane Electric Motor |
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Source: |
Cyclopedia of Applied Electricity, 1909 pgs 443-444 |
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Insert Date: |
11/10/2011 8:36:58 PM |
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Northern Electric Manufacturing Co. For constant-speed motors this concern employs the frames of their belted-type generators shown in Fig. 49, their ratings then being from ½ H. P. at 900 R. P. M. to 75 H. P. at 800 R. P. M. These machines are furnished for any style of mounting, any degree of enclosure, with back gearing or idler pulleys with spring tension. Series wound, they become varying speed motors, while with additional regulating or interpoles they become adjustable-speed motors with a speed variation of 4 to 1. Another line of motors manufactured by this company is their type S, built up to 50 H. P. constant speed and also a wide range of adjustable speed ratings with speed variations up to six to one and even greater if desired. The magnetic circuits in these machines are made of laminations, as shown in Fig. 94. The pole piece really consists of two independent magnetic paths, separated by an air gap between them. This prevents field distortion due to armature reaction and allows wide speed variation with sparkless commutation by simple field weakening. Fig. 95 shows diagrammatically the magnetic circuit from pole to pole. Although each pole is in two halves, the magnetic circuit in each quarter is complete without joints. They also manufacture a line of crane motors, as shown in Fig. 96. These are rectangular, dust proof, cast-steel frames, 4 pole, and series wound. |
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1909 Northern Electrical Mfg. Co., Type S Electric Motor Field
1909 Northern Electrical Mfg. Co., Type S Electric Motor Magnetic Circuit
1909 Northern Electrical Mfg. Co., Type S Crane Electric Motor
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