[X001M2AX], Letter from Wilson Stout Howell to Wilkes-Barre Electric Light Co, August 8th, 1889


View document with UniversalViewer   → Re-use this digital object via a IIIF manifest


[X001M2AX], Letter from Wilson Stout Howell to Wilkes-Barre Electric Light Co, August 8th, 1889

Editor's Notes

Gentlemen: Having now sufficient data on which to base an opinion I respectfully submit the following report of my inspection of your plant. ## My special attention was given to three features of the plant.: life of lamps, extension of lines and abandonment of feeder equalizers. ## Your troubles with lamps were of two kinds, short life and dull light, due to blackened globes, both of which were caused by abnormally high pressure. The highest pressure found was 121 volts, or ten volts above the normal of the lamps in use, the negative side of the system averaging four volts higher than the positive side and was due to the standard pressure indicator having gotten out of adjustment or changing its standard. This might have been caused by lighning or by a cross on the lines. ## The effect of high pressure is to increase the candles power of the lamps and to weaken the filaments, some of which break in a few hours, other live a reasonably long life but are so strained that they blacken the globe and give out a dull yellow light. ## When lamps have been injured by high pressure the only remedy is to change your lamps to a higher voltage, that is to say instead of decreasing your pressure on the lamps let it remain high and order all future lamps of a voltage suited to that high pressure, for, if your high pressure of 121 volts gives a poor light from the injured lamps a reduced pressure would afford still less light. Your Superintendent, Mr. Eberle, ordered a few lamps while I was at Wilkesbarre, of 115 volts, and we set the pressure at the standard indicators to gie us 116 volts, being a reduction of one side of the system of four volts below the average height of pressure on that side, and making no change of pressure on the opposite side of the system. With a pressure of 116 volts at the feeder ends the 115 votls 16 C.P. lamps gave a better light (clearer and more power) than the black lamps of 20 C.P. If lamps of 115 volts will satisfy all your customers you should continue to use that voltage, but if any complaint is made, and your pressure is knkown to be correct, 16 volts) you might order lamps of 114 volts but do not allow the pressure to be increased to either purposely or by accident. ## The lamps should always be suited to the pressure and the pressure should be kept constant and closely regulated. With a pressure of 116 volts and lamps of 114 and 115 volts you should have good life of lamps and very little trouble from discolored globes. ## Lamps discolor from being forced by high pressure, or from extreme long life at a proper pressure. Blackened lamps should be replaced by new ones and treated as if they had burned out. The light from a black lamp is often less than one-third of its rated power and their use is very bad economy. The extension line to South Wilkesbarre can be done on the three-wire system with good average economy by using the split 'bus now in operation at Philadelphia. The advantages of this plan over the converter system or the motor-dynamo device are greater economy and less investment. MR. Jenks of the Standardizing Bureau will furnish you all the figures and data to enable you to do your own work on this extension. For a distance of three miles or greater the motor-dynamo or converter system with continuous currents would perhaps be preferable. We have lately gone into this matter for other stations and the above conclusion is the result of careful experiment and calculation. ## The equalizer problem can be settled by yourselves and I feel certain that with an intelligent study of results you can abandon your equalizers before your winter load comes on. ## A system to be operated without equalizers must have heavy mains, many feeders, small loss in feeders and well balanced mains. Your mains appear to me to be heavy enough; your feeders are not far apart. I do not think your feeders are working at a large loss, there was less than a maximum of 5% when I measured the loss in June with 410 amperes output on each side of the system. Your balance was not bad nor was it remarkably good, and although with a summe load the balance did not interfere with the regulation I cannot tell how it may change with full winter load. ## As far as I can learn you are in a very fair condition to undertake to operate the station without equalizers and I would advise that you proceed as follows: Keep the equalizers in position ready for use but all turned out of circuit. Carefully observe the change of pressure at the indicators and if any indicator runs low or high, go to the end of that feeder and add load to the side having high pressure of take load from the side showing low pressures. In order words, balance the mains and the pressure will balance itself. If the balancing of the mains causes both indicators of one feeder to go high or low the main leading from that feeder to other feeders should be increased in size so that the load could be more equally divided between the various feeders. It would cost but a small amount to add a new feeder to your system to serve current to the corner of the square nearest to the station. Three number 4. B.W.G. wires, one for each conductor, would be large enough for that short distance. This new feeder would #5 and #2 feeders and decrease the loss at full load. IF #5 and #2 feeders hav a tendency to run high this new feeder would increase the fault but would correct any tendency of these two feeders to run low. ## If by balancing the load on the mains, adding a new feeder or increasing copper in one or two mains does not enable you to keep your pressure constant without the use of equalizers I will make another visit to your station and endeavor to determine the reaons.





Folder/Volume ID


Document ID



Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University
Download CSV | JSON