Generator general principle mechanical energy converted in to electrical energy.
A car generator is a DC motor. If you apply power to a working DC motor, it will turn the armature and produce work. If you turn the armature of a working DC motor, it will produce power. Generators in cars were replaced during the early 1960's with alternators.
DC generators require more time and material to make. Because of this, it will be cheaper to purchase an AC generator. DC generators are typically a better product as well, and you get what you pay for.
Windstream Power and several other companies like it sell DC generators. You can buy them online or there are several stores where DC generators can be purchased. There do not seem to be any stores which sell them locally, but you can buy DC Generators online at http://www.windstreampower.com
DC generators are always useful in case of power outages. Many commercial companies use generators as back up units. DC generators are also energy efficient.
Most diesel generators are designed to produce alternating current (AC) electricity. However, there are some diesel generators that can also produce direct current (DC) electricity with the help of rectifiers or inverters.
There are several online stores selling DC generators. Many household appliance store will also have generators.
A fans blades are driven by motors. Since there are both AC and DC motors, fans can be AC or DC. The fans in your computer are DC fans. Your ceiling fans are AC fans. (Thanks for fixing my answer)
DC generators are always useful in case of power outages. Many commercial companies use generators as back up units. DC generators are also energy efficient.
Batteries and generators provide DC, Direct Current electricity.
AC generators have a varying waveform which is sinusoidal in nature, whereas a DC output is linear.
The two main types of generators used to produce electricity are AC (alternating current) generators and DC (direct current) generators. AC generators are commonly used in power plants and homes, while DC generators are typically used in portable devices and certain industrial applications.
you apply dc voltage to slip rings in synchronous generators polarity will make no difference ( other than when it is first applied )