FORD VAN POINTERS.
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By R. T. Nicholson (Author of "The Book of the Ford ").
IN MY last set of Pointers (sounds doggy that, somehow!) I dealt with possible ignition troubles leading to bad starting. Now we come to a more elaborate question calling for a more complicated answer. I am asGd how a Ford battery can be charged from an electric light supply—if it can be so re-charged.
• Recharging the Battery.
Let me say a preliminary word or two.
When a van is used regularly on long country daylight rounds, and the power starter is not overworked, the running of the engine ought to keep the battery in good condition, without special charging from any other source.
On the other hand, if the mileage of the van, in a longish period is small, or if the: lights and power starter are much used, the battery may fall below par and be chronically in a low condition. Then it will be the better for being occasionally charged from some outside source of current. In any event, it will be none the worse for an occasional full Charging, such as can be got by connecting up with an outside source of supply. As regards mileage, use of lights, and use of power starter, one cannot be definite "to the doe" I cannot tell you how much mileage in a given time is needed to keep the battery in good trim ; nor can I decide for you exactly how many hours' light you can draw in a week, or exactly how often—or seldom—you ought to use the power starter. Conditions vary a good deal. Twenty miles' driving in certain conditions will charge your battery better than twenty miles' driving in other conditions. The capabilities of generators vary, too. One generator charges better than another. So I can lay down no hard-and-fast rules for you. There is only one real test of battery condition—the hydrometer test.
I have long since told you all about this. I will here only state that when the battery is in tip-top condition, the reading on the hydrometer scale will be between 1.270 and 1.290. (A higher point than 1.290 iS rarely reached.) The best time to test is after a decent daylight run of, say, 50 miles—not after a, lot of" self-starting" or after long use -of the lights. It is best, too, to make, say, half-a-clozen tests at different times, and not to rely upon one test. lithe hydrometer reading is then chronically low—under 1.270, say—an occasional "
freshening" charge is desirable. If you have a suitable electric light or power supply at hand, you can give this freshening charge yourself provided that the supply is direct and not alternating. You cannot charge a battery from alternating current, for precisely the same reason that you cannot charge your battery off your magneto. The magneto gives alternating current; your generator gives -direct current.
True, you can, by special means and apparatus, convert an alternating 'current into a -direct current, but this is a " finicking " job for an amateur, and he is not likely to be able to get the special apparatus r uired..
First, therefore, find out whether your supply of current is alternating or direct. The supplying company will tell you this.
Even when you knew this, however, I should advise you to get the help, of an expert the first time. you set about the re-charging job. It is none too simple, and you can quite well make mistake's, as you will see when you read on. If you watch him closely, and ask a few intelligent questions, you will know how to do the work for yourself next 'time.'
Your expert (as well as yourself) should act on tin following instructions :—
Add Water.
I have told you long ago that you ought to keel the liquid in the battery cells high enough to cover— and just more than rover—the plates. It ought to in up to the level of the bottom of the filler tubes. Act clean distilled water (no other) to.bring the level ur to the right point. This is called "topping." I assume that nano of the battery liquid has beer spilled. It can only have been spilled' by carelessness. The addition of water, as described, is needed to make up loss by evaporation—which always .goet on. None of the'acid in. the liquid evaporates—only the water.
Reducing Amperage of Supply.
The volume of the current taken from a company's supply is always too great4to be run, direct to the battery. It must be reduced by passing the current through lamps or electric radiators before it reaches the battery. Otherwise the current will ruin the battery. These lamps or radiators provide the necessary resistance, whereby the amperage is reduced. The following is a/diagram of the necessary connections
The current passes from the-charging main through one lead of the double pole switch and fuse, then through the resistance. In this case a set of four lamps is shown, but a radiator may be used. The valves in the centre of each cell will be referred to later.
Now do not be in a hurry to connect up. Get a clear understanding first on every point involved.
Your resistance must be such as to take 1,200 watts on 200 volt mains, 600 watts on 100 volt mains, 300 watts on 50 volt mains. Exactly how many watts your lamps or radiator will take will depend on the construction of the resistance.
The normal charging rate -of the Ford Exide battery is 6 amperes. No more should be passed through. Sufficient lamp or racliator resistance must be provided to reduce the amperage to that point. If lamps are used (these being generally thee'rnost convenient forms of resistance), enough af them should be introduced into-the' circuit tolrepresent 150 candlepower on 100 volt mains, or 300 e..p. on 200 volt mains, if carbon filarnent'lamps are used. If -metal filament lamps aremsed, 450 cep or 900 c.p. must'be respectively the total of the c.p. of the lamps introduced. (Near enough is .good enough in the latter ease.) Notice direction. of the current. The connections must be such that the positive charging wire,(POS) runs to positive terminal of the battery, and negativa
tonegative. If the connections are reversed; much damage will be done to the battery. You can find out which is the positive and which is the negative pole of your supply by doing as follows: Connect up copper wire. with the doles of your outside supply, and dip the two into a vessel of water, to whieh a teaspoonful of salt has been added, keeping the two wires in the water at least an inch apartIf they lie close together, you williget a short,—which you do not want. The negative wire will be indicated by bubbles forming on it. (This is the effect of electrolysis, but do not worry as to what that means.) Connect up the negative wire, thus identified, with the negative terminal of your battery. Now note that the current passing through the positive wire must:pass through the resistance lamps in parallel, not in series. These arexhighly technical terms, but they mean only that there must be separate.passages for the current through each lamp, not merely one passage through all the lamps. The illustration. shows what is meant. Make the other positive connections shown.
'Ware Flooding.
Inside the filler tube of each cell "(3) is a valve, which is provided to prevent flooding when charging is going on. By flooding, I mean upward spurting of the liquid in each cell. In ordinary circumstances —when no special charging is going on—the valve will lie like this:— The valve can be turned into its proper position with the tip of the filler plug, which is shaped for the purpose. Set the valve at right angles to its ordinary position. Keep filler plugs tightly in place when charging is going on. During charging, the temperature of the electrolyte (the battery liquid) must not rise higher than 110 degrees Fahrenheit. If it does, insert more resistance in the circuit, or stop the charging for the time being till temperature has fallen. Make frequent tests with thermometer, especially if you find the temperature rising above the danger point early in the charging process,
Hydrometer Tests.
Also make frequent hydrometer test i once the battery liquid begins bubbling. There is no purpose in testing till bubbling begins. See next paragraph.
Time Needed.
I cannot tell you exactly how much. time will be needed for the charging process. It depends on the condition of the battery. The charge is complete when all cells are gassing (i.e.' bubbling) freely and evenly, when the gravity (as shown by hydrometer test) is between 1.270 and 1.290, and When oontinued charging over five hours will produce no higher test reading. At least'ifive hours' charging may be re-j quired to produce this maximum, and it may be more.
Expert Work.
Again, would emphasize the fact that-battery recharging is not an amateur's job thelfirst time the amateur wants to do it. If the expert attends to the details above set forth, and thegamateur watches to see how he attends to them, there ought to be no difficulty in the job for the amateur when a. second re-charging is needed.
In any event, I do not advise the amateur to attempt to give the first charge--7i.e., the first loading given when the battery is quite' new.