A power conditioner (also known as a line conditioner or power line conditioner) is a device intended to improve the quality of the power that is delivered to electrical load equipment. While there is no official definition of a power conditioner, the term most often refers to a device that acts in one or more ways to deliver a voltage of the proper level and characteristics to enable load equipment to function properly. In some usages, power conditioner refers to a voltage regulator with at least one other function to improve power quality (e.g. power factor correction, noise suppression, transient impulse protection, etc.). Conditioners specifically work to smooth the sinusoidal A.C. wave form and maintain a constant voltage over varying loads.

An AC power conditioner is the typical power conditioner that provides "clean" AC power to sensitive electrical equipment. Usually this is used for home or office applications and has up to 10 or more receptacles or outlets and commonly provides surge protection as well as noise filtering.

Power line conditioners take in power and modify it based on the requirements of the machinery to which they are connected. Voltage spikes are most common during power storms or other malfunctions in the main power lines. The surge protector stops the flow of electricity from reaching a machine by shutting off the power source.

A good quality power conditioner is designed with internal filter banks to isolate the individual power outlets or receptacles on the power conditioner. This eliminates interference or "cross-talk" between components. If the application will be a home theater system, the noise suppression rating listed in the technical specifications of the power conditioner will be very important. This rating is expressed in decibels (db).

The higher the db rating, the better the noise suppression. Good units start at a rating of about 40-60db for noise filtering. If a device does not state the db rating in its specs it may be better to move on to a different model or manufacturer.

The power conditioner will also have a "joule" rating. A joule is a measurement of energy or heat required to sustain one watt for one second, known as a watt second. Since electrical surges are momentary spikes, the joule rating indicates how much electrical energy the suppressor can absorb at once before becoming damaged itself. The higher the joule rating, the greater the protection.

See also:
Power conditioner
Custom Power Choices Abound
Voltage regulator labs, procedures and explanations

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