. The Street railway journal . ng a flatrecording surface. As the back pressure line is traced, theratchet G contacts with the toothed wheel under the drumA, causing it to rotate a fixed distance. This movement defines the distance between successive cards, and can takeplace at any point of the stroke desired. As the back pressureline is usually straight no error is introduced, and the cardspresent the same appearance as if taken singly. The operationis automatic, and records a card for each revolution, to theextent of the paper supplied by the drum B. Using thisdevice, two sets of indicator c
. The Street railway journal . ng a flatrecording surface. As the back pressure line is traced, theratchet G contacts with the toothed wheel under the drumA, causing it to rotate a fixed distance. This movement defines the distance between successive cards, and can takeplace at any point of the stroke desired. As the back pressureline is usually straight no error is introduced, and the cardspresent the same appearance as if taken singly. The operationis automatic, and records a card for each revolution, to theextent of the paper supplied by the drum B. Using thisdevice, two sets of indicator cards were taken on the enginerunning empty; one for a period of 2 minutes with an excitercurrent of 165 amps., and the other for a period of V/2 min-utes without the exciter. LEAKAGE TEST A leakage test of boilers, and boiler-feed and steam lines tothe engine throttle were made 36 hours subsequent to theofficial engine trial, said test being of 24 hours duration. Inconnection therewith, water was weighed and fed to the boilers. CONTINUOUS INDICATOR DIAGRAM DEVICE by way of the reservoir tanks, as in the engine test. Dueallowance was made for all known leakage and drips, and cor-rection made for change in boiler level. RESULTS OF FRICTION TRIALS (ELECTRICAL METHOD) i. Volts armature by switchboard meter, 10,510 volts. 2. Amperes armature by switchboard meter, 119. 6 amps. 3. Amperes field by Weston standard, 202. amps. 4. Kilovolt amperes armature 3 X (0 X (2)> 2170 k. v. a. 5. Power factor, (6) -^ (4), Per cent. 6. Kw input, X I00> 402-5 kw. 7. PR on test ()- X (n), kw. 8. PR at full load (263)= X (). kw. 9. Difference between (7) -(- (8), kw. 10. Total losses (6) -|— (9), kw. 11. Resistance of armature at 30 degs. C, 2877 ohms. The value kw is therefore added to all full load out-put readings, to obtain total load on the engine. RESULTS OF FRICTION TRIALS (CONTINUOUS INDICATORMETHOD) 1. With exciter current, engine emp
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectstreetr, bookyear1884
