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How Do Run Capacitors Work?

A capacitor, also known as a condenser, is a component in electronic devices. It consists of a combination of three objects. First, a pair of objects called conductors conducts electricity. The conductors are separated by a dielectric, which is a substance that does not conduct electricity. Common dielectrics include substances such as paper, ceramic and plastic.

How Do Run Capacitors Work?

When an electric current exists between the two conductors, it creates an electric field in the dielectric, which can then store energy. The most effective capacitors employ conductors that are wide and flat, as well as being perfectly parallel, with a very small distance between them.

A run capacitor is a particular type of capacitor. A run capacitor uses the charge stored in the dielectric in order to boost the electrical current providing power to an electric motor. This type of capacitor is created to maintain a charge during constant use of the motor. These capacitors are often found in devices, such as heaters, that are continuously running.

One variety of run capacitor is often used in air conditioners. This type of run capacitor is called a dual run capacitor, and uses two run capacitors for two different functions. In an air conditioner, for example, one run capacitor is used to boost the fan motor, and another is used to boost the compressor motor.

Run capacitors typically are classified at 370 or 440 volts. It is necessary to ensure that the correct rating of run capacitor is installed in an engine. If a run capacitor with an incorrect voltage rating is installed in a motor that requires a capacitor for second-phase energy, it will throw off the magnetic field. An uneven magnetic field will cause the rotor to slow in the uneven spots, which increases energy noise, as well as power consumption, and can also cause performance problems and overheating issues.