How does the armature get the initial charge in a generator. What makes the armature wiring magnetic?

Answer 1

Normally there is small amount of residual magnetism in the armature. This is usually adequate enough to build up voltage upon start up. The residual magetism is stored in the soft iron components of the armature. In small generators you may even have a small permanent magnet which by itself is not strong enough to generate full voltage but augments the regulated electro magnetic field .

In cases where a generator has been sitting idle for an extended period, the residual magnetism may fade (become weak) to a point where it is insufficient to cause a voltage build up at start. When this happens a technique known as "Flashing" the generator is done. Flashing uses a small battery to momentarily apply power to the field windings. This established a small magnetic field from which a voltage can build up from.... The ship service generators I worked on had a Flashing circuit built in to the switch board. A push button was all that was needed to apply power from a battery and flash the generator if necessary

Answer 2

Residual magnetism is enough to start the process. Once its started and voltage is present, this voltage produces a current in the winding.

If the residual magnetism is not there, a voltage can be applied to start the process off. This is usually called flashing because you don't want to keep the battery connected so you touch the wire briefly, this causes a spark.

Answer 3

There has to be a residual magnetizm to start the process. In the old days, if you installed a new generator in your car, you had to "spark" the armature with 12V. This would magnetize it.

Answer 4

If you make a coil of wire and apply a current or pulse of electricity, it becomes magnetic. In the case of a gasoline powered generator this can come from the battery used to start the engine, from a magneto attached to the shaft if pull started or from a piezo electric circuit which generates a pulse when squeezed. In the case of modern units, some have permanent magnets which generate a starting current that is enhanced by electromagnetism as it comes up to speed.

Answer 5

Steven F is not quite correct, you induce a voltage, not a current, and current will only flow if the wire is part of a closed circuit, you cannot move a piece of wire through a magnetic field and induce a voltage if it's not connected to anything.

Answer 6

ANY time an electrical conductor moves relative to a magnetic field, a current is induced. This is covered in grade school science class. At least is used to be. No 'initial charge' is required. Any engineer giving a different answer is over thinking the question.