Document xzN3kDk5G7b8Q9jVZObBBYK3y

Motors and Controllers GENERAL ELECTRIC COMPANY SCHENECTADY, N. Y. Sales Offices in Principal Cities Motor Drive and Control For Heating, Ventilating and Air Conditioning Systems Methods of Drive Fig. 1 Fig. 1. Silent chain drive can frequently be employed to advani ge, with a lowering of the motor cost as compared with direct-connected drive. The illustration shows a 25 hp., 500/900 r.p.m.. Type CD, adjustable speed, motor driving an American Blower Fan at the Port land (Oregon) Journal Building. The chain drive is enclosed in an oil-tight housing. Fig. ft Fig. 2. " Texrope" drive makes pos sible the placing of the motor very close to the fan pulley, and saves space. The ill straiion shows a 60 hp., 850 r.p.m. motor driving a Buffalo fan. The maximum an speed is 140 r.p.m. Fig. 4. With fans of moderate size driven by alternating-current motors, the simple belt drive is efficient and economical. This illustration shows a Type KT, 3 hp., 860 r.p.m., con stant speed motor controlled by a CR7005 magnetic switch, operating a Buffalo fan in the Plaut Store, Newark, N. J. Fig. S Fig. S. The directconnected, slowspeed direct-current motor has long been a standard drive for ventilating and ex haust fans in large Fig: 5. The center distances on a belt drive can be shortened by using the " Lenix" idler to insure a larger arc of contact at the motor pulley. The illustration shows a 10 hp.. Type MT, slip-ring induction motor driving a fan at the Washington High School, New Rochelle, N.Y. buildings. It is quiet and compact in operation, and has the lowest pos sible maintenance for a long period of years. The illus tration shows a Type CD, 15 hp., slow-speed, adjust able speed motor driving an Ameri can Blower fan at the Detroit Masonic Temple. Fig. 5 This Company wilt gladly assist in the solution of any electrical problem in relation to heating and ventilation 554 General Electric Company Motors and Controllers Motor Drive and Control For Heating, Ventilating and Air Conditioning Systems Controllers for Use with Varying Speed, 3- or 2-phase, Alternating-Current, Slip-Ring Motors for Driving Fans Remote Indicating Control Four Speeds--CR7761-FI Fig. 1.--CR7761-FI, 20-50 Hp. HP. Dimensions in Inches (Approx.) Height Width Depth Net Weight in Lb. (Approx.) 5- 7i/2 10-15 20 25 30 40 50 *67</i *671/2 *67'/2 67`A 67</, 67V? 67V? 36 36 36 36 39'/2 391/2 39'/2 37 37 37 37 37 37 37 ^ 360 375 475 575 650 725 850 All sizes mounted on 64-in. angle supports. Equipment includes one CR7761-F1 control panel, one BS-15-F four-speed indicating station, one BS-31-A start-safe-run station and one CR1924, 3-pole, fused switch. Dimensions of BS-15-F are 8 in. by 153 in. Sizes 5-15 hp. have self-contained resistors; Larger sizes have separate resistors. Remote indicating control, four speeds, operated by remotely located push-button station with bull'seye lights of different colors indicating speed selected or attained. 5-15 hp. CR7761-F1 and BS-15-F. CR7761-F1 enclosed contactor panel includes four speed-controlling or accelerating contactors with three relays. Remote located push-button station BS-15-F has four speed buttons marked (1) Slow Speed, (2) Second Speed. (3) Third Speed, (4) Full Speed, and one "stop" button. On pressing any "speed" button the motor accelerates auto matically to that speed and the corresponding bull'seye is illuminated. Speed can be changed while run ning to any other value by pressing button corre sponding to speed desired. An additional control sta tion BS-31-A with three buttons, "start." "safe," and "run," may be pro vided adjacent to the motor to start the equipment at the motor for test purposes. When the "safe" button is pushed the equipment is not only stopped but Fig. 2.--BS-15-F cannot be started from the remote indicating station. The "run" button on the BS-31-A station adjacent to the motor is pressed to release the "safe." When started by the BS-31-A station ad jacent to the motor, the motor can be run at slow speed only. If it is desired to arrange this controller so that the motor can only be started in the fan room, add a CR7002 and a BS-79-J Start-Stop station. With this arrangement the BS-31-A station will not be required. Speed control and stopping may be secured from the remote station as before. Fig. S Installation of 3 BS-15-F, Remote Indicating Control Stations for CR7761-F1 Controllers operating Exhaust Fans tn the Pent House of the Salaam Temple, Newark. At right is shown a Type MT Motor belted to Supply Fan and Controlled by a CR7764 Controller This Company will gladly ass electrical problem in relation 1 555 Fig. 4 Installation of Type MT Motor belted to Exhaust Fan at Salaam Temple, Newark. Motor is con trolled by a CR7761-F1 Remote Indicating Control Panel operated from a Remote Point by one of the Control Stations shown in Fig. 2 t in the solution of any heating and ventilation