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his place. When you have a continuous parade of engineers and firemen passing through your plant you can make up your mind that there is something radically wrong.

The education of your inside men might with profit include ! some position that brings them into contact with the public. To a switchboard-tender who has a realizing sense of the kicking capacity of several thousand customers, voltage variation means more than the trifling deflection of an instrument-pointer. The engineer who knows how long thirty seconds of darkness really are in a crowded store or theatre is most likely to double his watchfulness at critical times.

Nevertheless, in spite of all that may be done to prevent them, accidents happen, for there are many conditions that come to you as unsolicited as original sin; but every accident that does happen must be considered as an opportunity for improvement. Experience as a teacher is the highest salaried officer of your company, and you are not worth your hire unless you profit to the full by every lesson she gives you.

Fixing up a thing to be as good as it was before it was broken is merely setting up again the trap in which you have once been caught.

Do not stick your head in the sand and call a thing queer. Things are queer only to the lazy, the ignorant, and the man that is afraid to know. There should be nothing more galling to the superintendent than the consciousness that he does not know why a thing happened-know the most minute detail of the cause.

The answer to the question "What caused it?" must be pursued with relentless energy—with the persistence of a six-year-old boy. In the full and complete answer lies the way to salvation.

When you have solved the problem and have conscientiously applied the proper remedy to the case in hand, the next thing to do is to hunt up every other place where the same thing is likely to happen from the same cause and apply the remedy there before the trouble comes. When a thing happens for the first time, you may have the consolation that it is an accident in the true sense of the word, but when it happens the second time you know in your heart that it is really something worse. If the justly celebrated follow-up system of our new-business departments is of value anywhere it is in the following up of an accident. Follow it up to the bitter end every time. The more thoroughly you do it, the less of it you will have to domand, I admit, it is not a very agreeable occupation.

The persistent carrying out of this plan will eliminate to a great extent those exciting moments when everybody has ro be "on the jump.” Remember, the utter absence of the need for hurry is immeasurably preferable to the most brilliant exhibition of it. The man that skips over an accident with the remark, "Oh, that's nothing! Little things like that happen every day; we can't help it !" is a dangerous man to have around. He has arrived at the same mental state reached by the copious liar when he begins to believe himself.

Complaining about the stupidity of your help but proclaims your own. Patience and persistence must be your watchwords. Repetition may be tiresome, but the truth has nerves of iron and can stand it. You can not merely give instructions and then go to bed; you must stay up more than once if you want to see them carried out. Electric lighting is a continuous performance with a vengeance.

However, no matter how much care you give it, there comes a period now and then in the life of your equipment when the scrap-heap must be called into requisition. The manufacturers would fain persuade us that we must change our model every season-just as we changed our bicycles some years ago, or as our directors now change their automobiles. There lies great danger in extremes either way, and you will earn the mark of a genius if you can choose the correct psychological moment for a change.

For the last two years our new-business friends have been working at fever-heat. If you do not want their efforts to result in a mere glittering bubble that can be pricked unexpectedly, be sure that you are just a little bit ahead of them all the time. Put your house in good repair before you invite people into it. Do not hang out a gilded sign on a ramshackle shanty. Advertising a plant that has outlived its usefulness is on a par with feeding medicine to a corpse.

The strategy of an advertising campaign must be thought out from the coal-pile forward. Your high-sounding phrases, your art nouveau contortions, your agonized combinations of colors and ideas, will merely invite ridicule if your service is below standard. Remember that “Good Service” is the name of the solicitor who covers your whole territory every day and calls continuously on all your custonters with the one argument that is supreme.

Perhaps, gentlemen, all I have said may seem to you mere badinage, but, believe me, there is an undercurrent of stern truth that will bear close scrutiny and that will, I hope, merit your. attention.

THE PRESIDENT: Is there any discussion in regard to this admirable paper; so forcibly read by Mr. Martin?

MR. SCOVIL: I should like to give the gentleman a nickname—he ought to be termed the Ben Franklin of the industry, the maker of maxims and aphorisms.

THE PRESIDENT: If there is no discussion we will proceed to the next paper on the programme, Power-Factor Correction, by Mr. F. D. Newbury, of Pittsburgh.

Mr. Newbury presented the paper, as follows:



Alternating-current systems have generally-recognized and, in many cases, controlling advantages; they may have, on the other hand, one serious disadvantage not encountered in directcurrent systems--that of low power-factor. With the rapid increase in the industrial use of induction motors and in arc lighting by alternating current, the troubles incident to low powerfactor, in systems not designed for it, have become unfortunately familiar. It is the purpose of the present paper to point out the more inportant effects of low power-factor and to show how, in some cases, these bad effects may be overcome by the proper application of over-excited synchronous motors.

THE EFFECTS OF LOW POWER-FACTOR Low power-factor has two serious results: it limits the capacity of the electrical part of the system by loading it up with unproductive current-current for which no revenue is obtained ; and it means poor voltage regulation. Unproductive Current

When the power-factor is 100 per cent—when the current and voltage are in phase-all of the current is effective in doing work and the kilowatts, measured by a wattmeter, are the same as the kilovolt-amperes, measured by a voltmeter and ammeter. At power-factors lower than 100 per cent—when the current is not in phase with the voltage-only that component of the current that is in phase with the voltage is effective in doing work and only this component is measured by the wattmeter. The ammeter, however, measures the total current. factors lower than 100 per cent the kilowatts are, therefore, less than the kilovolt-amperes, the ratio between them being equal to the power-factor. The rating of electrical apparatus depends primarily on the heating produced by the load, and this heating

With powerdepends entirely on the current. The kilowatt load, therefore, unless the corresponding power-factor is taken into account, is not a measure of the actual load on the apparatus.

This has an important bearing on the relative ratings of prime movers and electrical apparatus. The capacity of prime movers is determined solely by the energy load as measured by the wattmeter. The capacity of electrical apparatus-generators, transformers or feeders-is determined by the kilovolt-ampere load, which, with a given energy load, depends on the powerfactor. The power-factor, therefore, should be taken into account in selecting a generator for a given engine. This, unfortunately, is done in very few cases. It is all too common to make the kilovolt-ampere rating of the generator equal to the kilowatt rating of the engine. The current load on the generator will only correspond with the energy load on the engine when the kilovoltamperes equal the kilowatts, which is at 100 per cent powerfactor. At lower power-factors, the generator will be carrying more load, relatively to its rating, than the engine. It is putting the matter very conservatively when it is stated that in less than half the power plants designed, has the power-factor been taken into account, as it should be, in determining the relative ratings of the engine and generator. This means that in a large number of plants it is only the large overload capacity of the generators that enables them to put even full load on the engines.

This unequal loading of the engines and generators is not the only bad condition due to this effect of low power-factor. The revenue of a station is affected. The revenue depends on the kilowatt load and not on the kilovolt-ampere load, since power taken by customers is measured by wattmeter. Therefore, with low power-factor the generators, transformers and feeders are loaded


with current that can bring in no revenue. In a system in which the engines have a kilowatt rating equal to the kilovoltampere rating of the generators and other electrical apparatus the revenue-producing capacity of the system is cut down in direct proportion to the power-factor. At 70 per cent powerfactor, for example, the revenue will be only 70 per cent of the revenue that could be obtained at 100 per cent power-factor from the same current and same investment in electrical apparatus.

Low power-factor, then, means that unless the system has

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