Twentieth century handbook for steam engineers and electricians, with questions and answers; a practical nontechnical treatise .. (1916)
Swingle, Calvin F. (Calvin Franklin), b. 1846 · Chicago, F.J. Drake & company · leaf 1260
for operating rheostat. 1 Eeceptacle for voltmeter plug 1 S. P.-S. T. field switch.* 1 S. P.-S. T. main switch. 1 Eecording Watt-hour meter. A rear view of these panels is shown in Fig. 552. *S. T. means single throw. D. T. means double throw, i. e., the switch has two setsof clips and can be… … Fig. 547d. c. generator panels 1226 Steam Engineering iSffiL
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