. Electric railway journal . intervals. I am speaking, of course, of those systems where ef-fort is made to attain thorough-going accuracy foundedupon a substantial basis. In this connection, however,it is worth while to point to the increasing use of themercury type of watt-hour meters. If charges betweenone electric company and another or an electric powercompany and a railway corrfpany are to be based uponmercury-type watt-hour meters the resistances of theshunts ought to be measured in situ. This measure-ment of the resistances of shunts after installation issomewhat difficult and complica
. Electric railway journal . intervals. I am speaking, of course, of those systems where ef-fort is made to attain thorough-going accuracy foundedupon a substantial basis. In this connection, however,it is worth while to point to the increasing use of themercury type of watt-hour meters. If charges betweenone electric company and another or an electric powercompany and a railway corrfpany are to be based uponmercury-type watt-hour meters the resistances of theshunts ought to be measured in situ. This measure-ment of the resistances of shunts after installation issomewhat difficult and complicated. In large stations orsubstations it is a matter needing not only proper in-strumental testing equipment but considerable skill. There Is Work on Gages toBe Done Also Turning to the steam plant, and considering testswhich may be called necessary, the pressure gagesnaturally come in first for attention. There are indeedother ways for a manager to be assured that steampressures are really what the station log indicates than. The heart of the power plant—the accuracy of every meter mustbe checked carefully to have a testing force to calibrate steam gages. Butit is true that in a large station where there are manygages the average of accuracy is apt to be low unlessan organized testing force is looking after them. If such gage testing is done it is naturally done allalong the line—water gages, air pressure and draftgages, vacuum gages, etc. In a large station with con-siderable instrumental equipment, maintenance andcalibration of such instruments have just about thesame status as in the case of electrical instruments.)That is, to a considerable extent repairs are made bythe testing force, and the general maintenance of in-strumental accuracy where repairs are not necessaryprovide a considerable amount of work. To specifydefinite instruments may seem to be criticising certainof them, but broad experience will not lead to such adeduction. If there is a plentiful supply of ste
Size: 1670px × 1497px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublishernewyorkmcgrawhillp
