Soderholm L.H., Puckett H.B. Selecting and Using Electric Motors

Farmers' Bulletin 2257. — Washington: US Department of Agriculture, 1974. — 56 p.Electric motors are an efficient, compact, and dependable source of power. Effective use, however, requires the selection of the best type for a particular job, proper installation, and the use of suitable controls for the operation and protection of the motor. Alternating-current motors designed to operate on 115 or 230 Volts, 60 Hertz (cycles), and single-phase service are generally being used on farms. However, three-phase motors, particularly in the larger horsepower ratings, are becoming more common as three-phase power or the use of phase converters makes their operation possible on rural power lines. Special-purpose motors are sometimes installed by manufacturers as an integral part of their equipment. These motors usually have characteristics that are not suitable for general-purpose use and are not considered in this bulletin.Single-phase motors.
Split-phase motors.
Capacitor motors.
Capacitor-start motors (CS-IR).
Two-value capacitor motors (CS-CR).
Permanent-split capacitor motors (PSC).
Wound-rotor motors.
Repulsion-start induction motors (RS).
Repulsion-induction motors (RI).
Repulsion motors (R.
Shaded-pole motors.
Universal or series motors (UNIV).
Synchronous motors.
Soft-start motors (SS).
Three-phase motors.
Variable-speed motors.
Phase converters.
Motor selection.
Electrical service.
Single-phase.
Three-phase Effects of voltage and frequency on motor performance.
Motor torque characteristics.
Motor loading.
Temperature.
Operating conditions.
Enclosures.
Bearings.
Motor ratings.
Installation a nd wiring.
Causes of motor failure.
Mounting.
Connecting to the load.
Wiring.
Wire sizes.
Connections.
Motor protection and control.
Protection.
Fuses.
Other overload protective devices.
Controls.
Manually operated switches Magnetic motor starters.
Servicing and repair.