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Frequently Asked Questions

This section is for informational purposes only and should not be used as a design tool or to generate technical specifications. For further details, please contact CTI and discuss with a representative for clarification. Search for terms or questions by entering words or phrases in the text box and clicking Search, by selecting a category from the drop-down list and clicking Show. Then simply click on the linked term or question below.

Question: What is a Line Reactor?

Answer: A line reactor is a special form of inductor that is typically used between the line and the load to smooth current inrush, reduce harmonics and noise, and buffer the systems connected to it. Specifically it is an inductor that adds inductive impedance to a circuit. These devices are available in either single phase or three phase configuration, with three phase units being the most common, and are connected in series to the load which they are protecting. line reactors are typically specified as a percent impedance at a certain voltage and current level. For example, a 480 volt, 5%, 25 amp, line reactor is a typical specification. This specification means that a 25 amp load current the line reactor will have a 5% inductance impedance voltage drop on a 480 volt system. If the load is an inductive impedance load, the voltage to the load will be 5% lower than the voltage to the line reactor. If the load is a capacitance impedance load, the voltage to the load will be 5% greater than the line voltage input to the line reactor. If the load is a resistance impedance load, the load voltage will be less than 1% lower than the voltage input to the line reactor. Often line reactors are used in circuits to replace considerably larger and more expensive drive isolation transformers.

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