Part 41 (1/2)
A correct charging rate is one which keeps a battery fully charged, but does not overcharge it, and which does not cause either the generator or the battery to become overheated. The only way to determine whether a certain charging rate is correct on any particular car is to make an arrangement with the car owner to bring in his car every two weeks. On such occasions hydrometer readings should be taken and water added, if necessary, to bring the surface of the electrolyte up to the proper level. The hydrometer readings will show whether the generator is keeping the battery charged, and if a change in the charging rate is necessary, the necessary adjustments may be made. If a customer does not bring in his car every two weeks, call him up on the phone or write to him. The interest which you show in his battery by doing this will generally result in the customer giving you all his repair business, and he will also tell his acquaintances about your good service. This will give you considerable ”word of mouth”
advertising, which is by far the best form of advertising and which cannot be bought. It must be earned by good battery service.
Adjusting a third brush generator. The best rule to remember for changing the output of a third brush machine is that to increase the output, move the third brush in the direction in which the commutator rotates, and to decrease the output, move the third brush in the opposite direction. Move the third brush only 1/16 inch and then sandpaper the brush seat with 00 sandpaper. Allow the generator to run for about twenty minutes to ”run-in” the brush. Then vary the speed to see what the maximum charging rate is. If the change in the charging rate is not sufficient, move the third brush another 1/16 inch and proceed as before until the desired charging rate is obtained.
Adjusting Vibrating Regulators. The output of generators which use a vibrating regulator is adjusted by changing the tension of the spring fastened to the regulator arm. In many cases this adjustment is made by means of a screw which is turned up or down to change the spring tension. In other cases a hook or p.r.o.ng is bent to change the spring tension. Where a coil spring is used, lengthening the spring will decrease the tension and lower the output, while shortening the spring will increase the tension and raise the output.
Vibrating regulators are of the ”constant” current or the ”constant-voltage” types. The constant current regulator has a winding of heavy wire which carries the charging current. When the charging current reaches the value for which the regulator is set, the electromagnet formed by the coil and the core on which it is wound draws the regulator armature toward it and thereby separates the regulator points, which are in series with the shunt field. A resistance coil, which is connected across the regulator points and which is short-circuited when the points are closed, is put in series with the shunt field when the points separate. This reduces the shunt field current, causing a decrease in generator voltage and hence current output. As the current decreases, the pull of the electromagnet on the regulator armature weakens and the spring overcomes the pull of the electromagnet and closes the regulator points. This short-circuits the resistance coil connected across the regulator points and allows the shunt field current to increase again, thereby increasing the generator output. This cycle is repeated at a high rate of speed, causing the regulator points to vibrate rapidly.
The action of a vibrating ”constant-voltage” regulator is exactly the same as that of the ”constant current” regulator, except that the coil is connected across the generator brushes. The action of this coil therefore depends on the generator voltage, the regulator points vibrating when the generator voltage rises to the value for which the regulator is set.
Adjusting Reverse-Series Generators. The regulation of the output of this type of generator is accomplished by means of a field winding which is in series with the armature, and which therefore carries the charging current. These series field coils are magnetically opposed to the shunt field coils, and an increase in charging current results in a weakening of the field flux. A balanced condition is reached at which no increase of flux takes place as the generator speed increases, the tendency of the increased shunt field current to increase the total flux being counterbalanced by the weakening action of the flux produced by the series field current.
To increase the output of a reverse series generator, it is necessary to weaken the opposing series field flux. The only way of doing this is to short-circuit the series field coils, or connect a resistance across them. To decrease the output of a reverse series generator, a resistance coil may be connected in series with the shunt field winding. Neither of these schemes is practicable, and hence the reverse series generator may be considered as a ”non-adjustable”
machine. Under-charging may be prevented by using the starting motor and lights as little as possible, or by giving the battery a bench charge occasionally. Over-charging may be prevented by burning the lights whenever the engine is running, or leaving the lights turned on over night.
Other forms of regulation have been used on the older cars, but the majority of the cars now in use use one of the four forms of regulation described in the foregoing paragraphs. If adjustments need to be made on some car having a system of-regulation with which the battery man is not familiar, the work should be done in a service station doing generator work.
If generator outputs are changed because of some special operating condition, such as summer tours, the rate should be changed to normal as soon as the usual driving conditions are resumed.
TESTING AND FILLING SERVICE
Every man expects to be paid for his work, since his purpose in working is to get money. Yet there are numerous instances in every line of work requiring work to be done for which no money is received.
The term ”Free Service” is familiar to every repairman, and it has been the cause of considerable discussion and dispute, since it is often very difficult to know where to draw the Tine between Free Service and Paid Service.
The term ”Free Service” might be abolished with benefit to all concerned. In the battery business ”Free Inspection” service is a familiar term. It is intended to apply to the regular addition of distilled water by the repairman and to tests made at the time the water is added. Since the term ”Inspection” might be Misinterpreted and taken to apply to the opening of batteries for examination, the term ”Testing and Filling Service” should be used instead of ”Free Inspection Service.”
Battery makers furnish cards for distribution to car owners. These cards ent.i.tle the holder to bring in his battery every two weeks to have distilled water added if necessary, and to have his battery tested without paying for it. This service requires very little time, and should be given cheerfully by every service man.
”Testing and Filling Service” is an excellent means of becoming acquainted with car owners. Be as pleasant and courteous to the ”Testing and Filling” customer as you are to the man who brings in a battery that needs repairs. For this customer will certainly give you his repair business if you have been pleasant in giving the Testing and Filling Service.
A thoroughly competent battery man should be put in charge of the Testing and Filling Service, since this man must meet the car owners, upon whom the service station depends for its income. Customers are impressed, not by an imposing array of repair shop equipment, but by the manner of the men who meet them. These men will increase the number of your customers, or will drive trade to compet.i.tors, depending on the impression they leave in the minds of the car owners.
Every service station owner should persuade all the car owners in the vicinity of the station to come in regularly for the free testing and filling service, and when they do come in they should be given cheerful, courteous service. Each ”testing” and ”filling” customer is a prospective paying customer, for it is entirely natural that a car owner will give his repair work to the battery man who has been taking care of the testing and filling work Oil his battery. When a new battery is needed, the ”testing” and ”filling” customer will certainly buy it from the man who has been relieving him of the work of keeping his batteries in good shape.
Car owners who depend on your compet.i.tor for their ”testing and filling” service will not come to you when their battery needs repairing, or when they need a new battery. You may be convinced that you handle a better make of battery than your compet.i.tor does, but your compet.i.tor's word will carry far more weight than yours with the man who has been coming to him for testing and filling. Good testing and filling service is, therefore, the best method of advertising and building up your business. The cost of this service to you is more than offset by the paying business it certainly brings, and by the saving in money spent for advertising. Remember that a boost by a satisfied customer is of considerably greater value to your business than newspaper advertising.
A careful record should be kept of every battery which is brought in regularly for testing and filling service. If a test shows that one or more cells are low in gravity, say about 1.220, this fact should be recorded. If the gravity is still low when the battery comes in again for test, remove the battery and give it a bench charge. The customer should, of course, pay for the bench charge and for the rental battery which is put on the car in the meantime.
Battery manufacturers generally furnish cards to be used in connection with the testing and filling service, such cards being issued to the customers. A punch mark is made every time the battery is brought in, If the owner neglects to come in, this is indicated by the absence of a punch mark, and puts the blame for any trouble caused by this neglect on the owner if any cell shows low gravity, a notation of that fact may be made opposite the punch mark for the date on which the low gravity was observed. If the low gravity is again found the next time the battery is brought in, the battery should be removed and given a bench charge. If the bench charge puts the battery in good shape, and the subsequent gravity readings are high, no trouble is present. If, however, the low gravity readings begin to drop off again, it is probable that new separators are required, especially if the battery is about a year old.
The logical course of events in the testing and filling service is to keep the battery properly filled (at no cost to the customer), give the battery an occasional bench charge (for which the customer pays), reinsulate the battery when it is about a year old (for which the customer pays), and sell the customer a new battery when the old one is worn out. If some trouble develops during the lifetime of the battery which is not due to lack of proper attention, the customer should pay to have the repairs made. From this the battery man will see how the Testing and Filling Service pays. The way to get business is to have people come to your shop. Become acquainted with them, treat them right, and you need not wonder where the money is to come from.
SERVICE RECORDS
In order to run a repair shop in an orderly, business-like manner, it is necessary to have an efficient system of Service Records. Such a system will protect both the repairman and the customer, and simplify the repairman's bookkeeping. For a small service station a very simple system should be adopted. As the business grows, the service record system must necessarily become more complicated, since each battery will pa.s.s through several persons' hands. Battery manufacturers generally furnish service record sheets and cards to their service stations, and the repairman who has a contract with a manufacturer generally adopts them. The manufacturers' service record systems are often somewhat complicated, and require considerable bookkeeping.
For the smaller service station a single sheet or card is most suitable, there being only one for each job, and carbon sheets and copies being unnecessary. Such a service record has three essential parts: (a) The customer's claim check. (b) The battery tag. (c) The record card. Fig. 183 shows a service record card which is suitable for the average repair shop. Part No. I is the customer's claim check, Part No. 2 the battery tag, and part No. 3 the record card, and is 5 inches by 8 inches in size. The overall size of the entire card is 5 inches by 12 inches. Parts I and 2 are torn off along the perforated lines marked (A).