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          A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Alternator (Old)

Is a repair at all worthwhile?

Several conditions are attached to this kind of repair. First of all, the original price of the component must be determined, and be compared with the cost of a repair. The same procedure is valid for a good used spare part. The comparison with other generators is also interesting, because, in principle, a lot of different generators can be exchanged with each other, if one is talented in the adapting of mounting brackets. A different rotation direction can even be obtained by exchanging the fan wheel.

Better testers save time and determine more exactly.

Whoever desperately wants to put his energy into the repair, and not in the reconditioning of another current producer, can now read on. Should an oscilloscope or similar elaborate testing equipment exist, we refer with pleasure to the other sides of the generator. The hardest part is with the multimeter, e.g., when testing the voltage regulator.

Resistance measuring for windings and diodes

Figure 1 shows the stator windings and their three ends. The other three are connected, as everyone knows, with each other. If this connection cannot however, be found, one can still undertake resistance measurements on the three intersections (soldering points) of the diode plate. One always gets two windings, one after the other, and should obtain values in the one-digit Ohm area. The diodes right at the back can, in each case, through two resistance measurements, from the only connection to their casing with resistance and infinity, to some degree, be scrutinized.

Apart from regulators, everything is simple to recondition

The slip rings in figure 2 are pretty well worn out, and would have to be turned on a lathe. Please, check of course, also the carbon brushes in the regulator. Bearings can be quite reasonably obtained with the help of the printed number. The rotor winding has an even smaller resistance (approx. 10%) than the stator and can be tested through the two slip rings. Woe betide if the old dear has coil- or diode damages, which only appear in normal or hard-pressed operation. Do not give too much credibility to your measurements. 01/08               Top of page               Index
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Translator: Don Leslie - Email:

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