Hawthorne Works, Western Electric Co., Chicago, Ill.
Pages: 15 Published: Jan 1973
Data for drawing hysteresis curves were originally obtained by the point-by-point method which was tedious and time consuming. For this reason, devices known as hysteresigraphs for drawing hysteresis curves automatically were developed. The first models did not have power to drive a recorder pen; hence, photographic techniques were used to obtain a permanent record. Later hysteresigraphs used the galvanometer photoelectric amplifier to amplify the signal and thus obtain the power necessary to drive a pen and draw a hysteresis curve directly on graph paper. For satisfactory operation, the photoelectric amplifier must be elaborately shock mounted, and adjustments and repairs require experienced personnel. The all electronic hysteresigraph eliminates many inherent disadvantages of the earlier models and makes it possible to draw a hysteresis curve in approximately one minute.
hysteresis, magnetic materials, magnetic measurement, galvanometers, photoelectric materials, electronic test equipment, integrators, servomotors, recording instruments, measuring instruments, flux (rate)
Paper ID: STP36852S