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regulators to work and before they can take care of the voltage the load is off and the regulator must move back again. have had a great deal of trouble from that source, and in this connection one point has occurred to me. The ordinary spot welder takes about 20 kilowatts of capacity for that small service and it seems to me that it would be easy to handle a welder on a motor-generator set with a flywheel to carry the high instantaneous demands. The power could then be taken from a 3-phase circuit and operate a single-phase generator. The customer would of course object to the motor-generator because of the increased expense of installation, and if one company alone insists that these sets be furnished while other companies do not require them, the consumer will feel that he is being discriminated against and asked for something unnecessary. If some action could be taken by this body to get a motor-generator set specified as a part of the spot-welder equipment we would find that five horsepower would take care of them and in some cases three horsepower would be sufficient.

The longest time that I found a spot-welder in operation. was only about two seconds, and that on very heavy pieces. The average time on the ordinary spot welder is only a fraction of a second, an interval so small that we could not measure it.

A question has been asked about putting more than one spot welder on a circuit. In one case we installed a 20-kilowatt transformer to operate one spot welder. During the test it took thirty kilowatts, as nearly as we could measure it. Since then two more spot welders have been added to the same transformer and, so far as we can see, have made no difference. The diversity factor in the operation of the three seems to take care of that entirely. Just how many more could be added, it is impossible for me to say, but I have no doubt five or six such welders could be operated from one 20-kilowatt transformer.

MR. C. W. PENDELL, Chicago: We have a number of these spot welders on the lines of the Public Service Company of Northern Illinois and are not making any special provision for sizes up to about 30 kilowatts, but are taking them on along with the rest of a customer's power load, figuring that the motor-generator balancing action of the induction motors and fly-wheel action of general motor load will smooth out the fluctuations caused by the welder load.

We had one customer come on with an 80 kilowatt welder, which caused us considerable trouble. The customer built this welder from a number of special transformers purchased for another purpose and we did not know it was coming on, so could make no preparations to take care of the load In analyzing this load we found the power factor to be only about 30 percent, the 80 kilowatt, single phase welder giving us about a 270 kv a load on our three phase line. By remodeling the wiring on the low voltage side of the welding outfit, we doubled the power factor and halved the kv-a load on our line, which did away with most of the trouble this outfit caused us at the

start.

What I wish to mention particularly, however, in my discussion is a device that one of our engineers has developed and patented

Mr. Herz of our Company has developed a reactive dumny load which is switched onto and off the line as the welder is switched off and on, keeping the ky a load on the line practically constant The swithing is done so quickly that the bad flue tuations are very slight In another device, which is built on the principle of a magnetic regulator, you can take any size of welder and swing it onto and off the line with no fluctuation at all

We now have un fer const 'eration a proposed 200 kw on gle plase weller. You can magme what a welder of this size would do to the regulation on a line if taken on workout using some special device, such as t'at mentioned

As far as the rate for welder service is con ersed, we are classing welders in with general power loa's, there being no special provisions if customers install we'ders in such a nanner as not to cause finitimations on our lines

I think it would be well worth wide to have Mr Herz describe his outfit

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a voltmeter of the ordinary kind. The reactions, when the device is properly designed, can be made so that the total power consumption is but 5 percent of the load consumption. The scheme has been used and works and there has been no trouble connected with it in any way.

MR. OLTZ: What is the nature of the switch that transfers the load from the welder to the reacting coil or whatever is used for that load. If a reactive coil, what are its characteristics?

MR. HERZ: In one particular installation the load switch was a 400-ampere Westinghouse switch overloaded by about 100 amperes. We used a similar switch on the reactives, a load control switch, and the primary was controlled by a 600-volt three-way, snap-switch, so that the operator in snapping over from one position to the other operated the switches alternately, and the characteristic of this particular main switch, the 400ampere switch in the case, was that it came out considerably slower than it went in and consequently there was no lapse. They worked simultaneously as far as the eye or an ordinary meter could follow it.

I built the reactive up out of some scrap transformer iron. The water cooled the iron in that particular case and the copper was air-cooled. The iron losses were higher than the copper losses. We now have estimates and figures for the whole thing and the re-acts will be properly made and enclosed in an ordinary transformer case and cooled.

REPORT OF SUB-COMMITTEE ON COMPETI

TIVE POWER SOURCES

EF TWEEDY, CHAIRMAN

DISCUSSION

MR R. F. BENZINGER, Erie, Pa.: Will some gentleman please tell us how to meet successfully the problem of a gas engine operating on natural gas containing about 1000 Btu.'s and costing 30 cents a thousand cubic feet? We have in our territory a series of gas engines that are operating on a maximum load of three-fourths the rating of the engine. These engines are giving practically no trouble and we find it extremely dithcu't to secure this business I would like to hear from some one who has had to meet this situation.

MR. OLTZ: What is the rate? What is the power?

MR. BENZINGER: Why, on an engine of that size operating ten hours a day, it would be about 14 to 1

ing on the load.

cents, depend

A MEMBER: You can get it for about 14 cent.

Mk. A. W. Chitis, Los Angeles: I would not like to see the statement go into the record that way, namely, that the rate of half a cent would be necessary to get such business I am not clear as to whether the electric company is endeavoring to secure the business or to retain the business

MR. BENZINGER: We are endeavoring to get the business away from the gas engine,

MR. CHILIS: We are retaining business on a sinlar proposition in our irrigating districts at a rate varying from 1. to 2 cents per kilowatt against natural gas at 30 centy We already had the business Natural gas developed and me into competition with us and endeavored to se

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business, offering a rate of 30 cents, 1st thus far we have been able to hold our own against that rate

(SEE REPORT, PAGE 56)

MR. BENZINGER: We have had some success in a very few instances where we have been able to show a slight increase in production. We have not lost any business, but we have great trouble in getting business.

MR. CHILDS: There are so many conditions that enter into this and so many different classes of business and kinds of operation that a broad question of that kind would be very difficult, I think, to answer in a few words, but I do feel that our business can be held and should be held against that source of competition at a fair rate. We have many talking points and things in our favor aside from the rate itself.

MR. BENZINGER: I would like to cite a case where we were successful in installing an electrical installation in a mill which had been operated with gas engines at the 30 cent rate for four years. This plant was a silk mill containing spinning machinery. The test that was made showed that during the night operation, the speed of the gas engine dropped between 1 and 2 percent, and this loss of production capitalized on the volume of business that this company was doing showed a net monthly loss of slightly over $300. That was something to bring out, and we were successful in getting the business on that basis, but in a great many instances it is practically impossible to convince a manufacturer that he can increase his production.

MR. GEORGE B. MULLER, Paterson, N. J.: I believe it has been proved beyond doubt to the various mill owners, that where the speed of an engine fluctuates, it seriously affects the manufacturer of the product. The silk or the textile is not of the same value, and this argument is one which I personally would use. I would not try to compete with the price of 30 cent gas, but would take the initiative on increased production. It is true, there are many times when a salesman will come into competition with a rate, when probably his rate will not show to any advantage, but, in the case of variation in speed of the various isolated plants, versus the constant speed of the central station, I think it possible to prove the advantages of purchased electric power. The Committee has in a way classified the engines mentioned in their relative competitive value to purchased power. I would like to ask if any of the members have arrived, through experience or tests, at the depreciation and maintenance costs of

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