Electrical news and engineering . re and the local transformer may be con-nected to either of the duplicate trunk lines from the mainstation. These trunk circuits are of Xo. o B. & S. barestranded aluminum cable and the branch lines are of No. 2stranded aluminum. The three other transformer houses are of concreteslabs reinforced with expanded metal bolted to structuralsteel frames. Two of these stations have two three- phase 22s 13200-575 volt transformers instal-led at present. The primaries of these transformers are, ineach case, controlled by a 15000 volt automatic oil circu
Electrical news and engineering . re and the local transformer may be con-nected to either of the duplicate trunk lines from the mainstation. These trunk circuits are of Xo. o B. & S. barestranded aluminum cable and the branch lines are of No. 2stranded aluminum. The three other transformer houses are of concreteslabs reinforced with expanded metal bolted to structuralsteel frames. Two of these stations have two three- phase 22s 13200-575 volt transformers instal-led at present. The primaries of these transformers are, ineach case, controlled by a 15000 volt automatic oil circuit-breaker. The City Owns the \ radical departure is being made by the Board inthe supply of power to the various manufacturers in thatthey decided to purchase and supply motors to the cus-tomers. They adopted this unusual policy to expedite theinstallation of electric power in every case possible, to pro-mote ease of interchange of motors with changing condi-tions of load, and to make possible a system of thorough. Rotor of Synchronous Motor. care and inspection of motors. They felt, further, that ex-pert supervision over the installation would enable themto choose a motor with higher efficiency and power factorthan has been considered good practice under average fac-tory conditions in this country. In the squirrel cage induc-tion motor, the type in most general use because of its lowcost and rugged character, certain construction and oper-ating characteristics can only be obtained at the expense ofothers. High efficiency can only be obtained by the sacri-fice of starting torque and power factor. High power fac-tor can only be obtained at the expense of air gap andefficiency and by the use of the closed instead of the open-slottype of construction. Typical practice in this country hasproduced a motor with open slot construction to facilitaterewinding, and fairly high starting torque with its conse-quent lower efficiency and power factor. On the otherhand, European pra
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Keywords: ., bo, bookcentury1800, bookdecade1890, bookidelectricalnewsen20donm
