Stand the test generator is fairly expensive equipment, not available to every car owner, so some motorists prefer to do them with my hands. So device for the promotion of the generator can be built out of the motor with the clutch decommissioned industrial sewing machines that were previously produced at the Podolsk or Orsha mechanical plants.
It is preferable to use motors more power – 1 kW, 2800 Rev/min. With such a home-made stand you can measure the following parameters: operating voltage generator, the number of revolutions and the load current. In principle, it is possible to use other types of electric motors with pulleys under the belt corresponding to the generator. It remains to sum up to the generator to 12V, connect according to the diagram. Do not forget the external relay (if any), and weight.
Then start the engine and measure the voltage at the output of the generator. Check the alternator on the bench gives the opportunity to determine the status of the generator and its main characteristics nominal. It is necessary to observe a very important requirement is that the alternator brushes have to be carefully lapped to the contact collector rings, the rings must be clean. So, install the generator on the stand, turn the motor on stand, set with the help of rheostat output voltage of approximately 14V, and the frequency of rotation of the rotor – up to 5 thousand rpm.
After two minutes of operation in this mode, measure the amperage provided by the generator. A working generator will show at least 44 A. If the output readings will be significantly less, it could indicate problems in the windings of the rotor and the stator, damage to the valves, the wear of the slip rings and brushes. If you have any suspicions about the malfunction of the valves of the rectifier Assembly of the alternator, then check the amperage returns to preheat the generator.
Advice 2: How to make a generator from a motor
Most electric vehicles has the property of reversibility. This means that a motor can be used as generators. Exactly how, depends on the type of engine.
Before you use the motor as a generator, make sure that it is not supplied external power.
To generator became commutator motor with a permanent magnet on the stator, Unscrew it until about the thousands of rpm. He will begin to develop a pulsating DC voltage, the polarity of which depends on the direction of rotation. Do not connect filter capacitor or battery directly - if you stop the generator it will start to discharge through it. To prevent this, use a diode or relay reverse current. So the battery is not recharged yet, use the current limiter charging or relay-regulator.
Commutator motor with series or parallel excitation will turn into a generator with independent excitation. To do this, disconnect the stator winding, submit it to DC voltage from the battery, and then Unscrew the motor. Pull the collector DC voltage, the polarity of which depends on the rotation direction and the polarity of the voltage winding. The power consumption of the coil, much less power, which can be removed from the generator. When the voltage appears, you can switch the excitation winding powered by a generator.
It is very convenient to use as generators are stepper motors. They develop a significant voltage at a relatively low speed. Even bringing this engine into motion with your fingers, without using any performance-enhancing gear to make a light bulb glow, led. It has several windings, each of which can be removed alternating voltage. If you wish to turn it into a permanent, use the normal bridges.
Induction motor working as a generator by itself will not, because there is no rotor magnetic field. Take three of a capacitor of a few tens of microfarad. They should not be electrolytic, and mandatory paper. Turn on one of them between terminals for first and second phases, the second between the findings for the second and third phases, and the third between the terminal for the first and third phases. Connect the load only after the promotion of the generator. Remember that it produces the same high voltage as that for which the engine is designed.