[X001M2AF], Letter from Wilson Stout Howell to Edison Electric Illuminating Co (Williamsport), February 3rd, 1888
[X001M2AF], Letter from Wilson Stout Howell to Edison Electric Illuminating Co (Williamsport), February 3rd, 1888
Gentlemen:- I beg to present this report of my inspection of, and work on your plant. On my arrival, I found: First, - That your system of distribution was badly out of balance, both as to current and pressure, that is to say: much more current was being delivered through the negative wires than through the positive wires, and that the lamps on the postive wires averaged about thirty percent brighter than the lamps connected to the negative wires. ## The effects of this distortion are to cause excessive lamp breakage among those customers supplied from the positive from those on the negative wires. All the lamps subjected to not burn out at once; they are greatly damaged. The causes of the trouble were: 1. more lamps connected to the negative wires than to the positive wires. 2. faulty or unreliable pressure indicators which did not correctly indicate the pressure, and 3. lack of faithful and intelligent handling of indicators and equalizers. Careful inspection, and many changes of customers from negative to positive side of system, corrected the first fault, while it was found very difficult to secure; and almost impossible to maintain a true indication of pressure, for the reason that the system of indications the pressure was not the best, and that the indicators were inconstant, requiring frequent adjusting and standardizing, besides being so placed as to be badly affected by the variable currents passing through the dynamo regulators (each carrying about twenty-five amperes) Therefore I strongly recommended that the pressure indicators be replaced by a complete set of standard and comparative indicators, and that there location be changed to a point as far as practicable from all disturbing influences. This recommendation was endorsed by your Board, and the new indicators were installed on the opposite side of the engine room where they were found to be but slightly influenced by the dynamos, and the heavy currents carried by the bus. To overcome these influences magnetic shields were procured and placed upon four of the indicators, which were most affected, since which no disturbance has been noticed. The immediate results of the use of the comparative system of indicators were a more uniform and constant light, and a material reduction of the lamp breakage, not withstanding the rapid increase of load and the increasing hours of lighting, due to the shortening days and the holiday trade. ## One of the indicators of the comparative system, is the balance indicator is used, also as a galvonometer, so arranged as to indicate the proper time to put two dynamos in multiple, when it is necessary to do so. SECOND:- That your system of feeder equalizers was not properly proportioned to its work. All of the twelve equalizers were of the same size, and pattern, all of the same capacity, and resistance, although each pair had different work to do. One pair carrying as much as 275 amperes, while another pair carried only 40 amperes, yet there was not a particle of difference in any respect between them. As a consequence some equalizers were not able to carry their current while others did not produce any effect on the light when turned through their entire range. All these equalizers I condemned through their entire range. All these equalizers I condemned and procured from your company an order for three pairs of the dates pattern of equalizers ordered according to the rules of best practice, to carry the full load for which each feeder is intended, and each pair of ten times the resistance of its feeder. These equalizers were connected to the three heavy feeders and the twelve old equalizers were altered so as to make three pairs of equalizers of greater resistance, which were placed on the three smaller feeders. All the equalizers were removed form the engine room and placed in the loft above, the head or switches for same were removed and placed on the wall in engine room, and connected to the boxes by heavy insulated copper wires, thus avoiding the use of long pendant shafts, which are generally used when equalizers are placed in loft, with the advantage of case of operation, facility of inspection, economy in space, decrease of weight on floor, rigidity, symetry, and general convenience. Each equalizer switch is placed opposite its corresponding pressure indicator and each is lettered and numbered so that no confusion or mistake should occur in operating. Each new type equalizer has nineteen steps from its highest to its lowest point, and each re-constructed equalizer has sixteen steps in its entire scope so that the regulation is obtained by easy gradations, and without jumps or wide changes of pressure. ## An ampere meter has been placed on each of the outside wires of each feeder, which shows at all times the current delivered to the mains by the feeders. By these instruments is known: if a feeder is doing more or less than its share of the work, or if each feeders is balanced or not, and if not, to what extent it is out of balance. Each such ampere meter is placed directly below the equalizers switch of its own feeder so that changes of current, due to changes of pressure can be noticed and corrected. ## THIRD: That the dynamo regulators are at fault in more than one respect, - 1st, some of the coils were entirely corroded off by steam which came up through the floor. 2nd, the regulation was effected by too few steps making it quite difficult at times to keep dynamos alike when working in multiple. 3rd, the boxes being much larger than the new type interfered seriously with placing them where they belonged, the object being to locate all the indicating and regulating apparatus in one place so that all could be operated with a minimum of labor and time. For these reasons a set of special regulators was ordered which are in every respect an improvement on the old ones. Each regulator has been numbered to correspond with its dynamo to facilities operation and prevent confusion. ## FOURTH:- The main and balance ampere meters (the instrument which show the output of current) being of an old type, (which depend for their accuracy upon the constancy of a permanent magnet which is always unreliable, - at the best) were found to be badly out of adjustment and to change so much, that frequent re-standarization was necessary. By comparison with a standard instrument, those indicators were improved but in view of their incontancy the most important one, the main ampere meter, was condemned and a new type instrument of double its capacity, built on an entirely different principle, was ordered, and the other, the balance ampere meter was sent to the maker to be re-standarized, and when returned will be placed in a better position, where it will be less liable to be affected by outside influences. ## FIFTH:- Each feeder was composed of three conductors: positive, negative, and neutral, commencing at the bus and extending to its proper section of the mains, making for the six feeders, six positive, six negative, and six neutral wires. For the sake of simplicity and to save labor and copper, instead of connecting all dix of these neutral wires to the bus, the bus was extended out of the station building to the first pole and from that point the six neutrals were continued to their proper points, thus decreasing the number of wires in the station, and relieving the cupola of much strain, already to great. I also recommend that during good building weather a further change be made in the neutrals of heavy wire (say 0000) to each section of the city, arranged to all the neutral feeders wherever they were found on the same poles ever practicable and have removed all safety catches or leads from the neutral conductors in all parts of the system, excepting only the inside, or house wires. ## I also strongly recommen that all the open ends of the mains be connected by "bridges" or conductors not smaller than No 4 B.W.C. especially where marked in yellow lines on plan of city annexed hereto, and that either a new feeder or a sub-feeder be connected to the mains at the instrsection of East, Third, Penn and Vanderbelt Streets. The most satisfactory method of strengh and one negative, from No 2 feeder, about one third of its length back towards the station, to the above named locality. Watch the pressure at this point and if at any time it is above normal connect the new lines at end of No 3 feeder where it will receive only the normal pressure and act as a reinforced main. I also recommend that the mains on Willow Street be reinforced with two No 2 B.W.G. wires, one positive and one negative run from No 1, 2, and 3 feeders to the mains at corner of Willow and Court Sts and joined there. This point being about equidistant from each of thos feeders the added wires would act not only as reinforced mains but also as feeder bridges of balance wires and would materially aid the regulation of these three feeders, while producing the desired effect of keeping pressure up at that point which is now about three volts lower than the feeder ends during heavy loads. ## The lighting of the upper portion of the ciyt, especially at the Penn'a R.R. station, can be materially improved by extending No 4 feeder to the Cor of Edwin and Walnut Sts, at the same time increasing the size of the main on Wlnut Street, so that it will act as a heavy bridge from No 4 feeder to No 6 feeder, in which case the neutral wire can be removed from No 6 feeder, provided that the neutral of main on Walnut Street is not smaller than No 2 B.W.C. ## RESULTS: The immediate results attained by the alterations and additions hereinbefore mentioned are marked and satisfactory. The life of the lamps has been improved, while the light has averaged brighter and far more constant. The distribution has been much better since balance was restored. The pressure is kept at 114 volts at feeder ends, and ranges loss than 2% above or below normal. Frequent tests of pressure of one hour duration at times which load is greatest, and during increasing and decreasing loads (especially while the Academy of Music is lighted) show very close regulation. The balancing of the load has greatly decreased the difficulties of operating the station; as formally the dynamos were unevenly loaded, which, as dynamos were run nearly to their capacity might have produced disastrous results during the heavy loads and long hours of running during the holiday season. Much of the credit of close regulation is due to the employment of two boys, as operators, each on duty twelve hours, daily whose undivided attention is given to maintain a constant prossure at all points of distribution. No only are these boys carefully instructed how to keep the pressure constant, but they are strictly watched, kept at their work, and frequently checked yb readings of pressure on various parts of the systems, which shows whether they are attending to their work or not. The greatest range of pressure at any time found on the mains was at a time when an arriature burned out at station, but at other times tests of pressure have never developed a higher pressure than two volts above normal, even such small variation lasted but a very short time, being noticed and corrected promptly by the operator at station. I consider such close regulation; provided it is always maintained, capable of securing good life from the new typo Edison lamp, especially if my recommendations concerning bridges and reinforcments of mains is fully carried out. All of which I most respectfully submit.
Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University