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. The Street railway journal . SECTION OF ENCASEDSPRING POP SAFETYVALVE Electrical engineers who employ the portable standard in-struments in general use for the making of exact measure-ments of electrical quantities or in the conduct of tests, knowhow difficult it is to take accurate observations in those portionsof the scale where the divisions are narrow, and the conse-quent uncertainty regarding results and difficulty in checkingup a series of measurements taken with different fact that only a portion of the scale is accurately legible,. PORTABLE POLYPHASE WATTMETER and tha
. The Street railway journal . SECTION OF ENCASEDSPRING POP SAFETYVALVE Electrical engineers who employ the portable standard in-struments in general use for the making of exact measure-ments of electrical quantities or in the conduct of tests, knowhow difficult it is to take accurate observations in those portionsof the scale where the divisions are narrow, and the conse-quent uncertainty regarding results and difficulty in checkingup a series of measurements taken with different fact that only a portion of the scale is accurately legible,. PORTABLE POLYPHASE WATTMETER and that it is not always possible to have at hand instrumentsof the proper range to cover all capacities properly, make it attimes impossible to avoid the use of comparatively illegibledivisions; and, as result, the curve sheets of tests and tables ofmeasurements show irregularities which rob the work of allvalue. To obviate such troubles the department of standards of theWestinghouse Electric & Manufacturing Company has de-signed a line of portable instruments, three of which are illus-trated herewith. The assortment comprises voltmeters, am-meters and single-phase and polyphase wattmeters. The voltmeter is zero reading, this form having been foundmost suitable for measurements for which a voltmeter is this form the readings are determined by the deflection ofthe milled head required to bring the index pointer to instrument is made in two capacities, which in connec-tion with the very long, open scale enables the readings to betaken
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectstreetr, bookyear1884