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Three-phase reactance in CTO limiting air. CTO

Reattanza trifase in aria di limitazione cto.cto

The short-circuit limiting reactors made by Italweber Elettra are typically installed in series with the power supply line and provide for the reduction of short-circuit currents. Current reduction can also occur for other purposes, such as starting electric motors or highly inductive machines.

The main advantage of this type of ballast is that it is possible to install circuit breakers with lower short-circuit currents, saving significantly in terms of cost and device life.

Another peculiarity lies in having the way of reclosing the flow in air and not in a ferromagnetic core, which results in the absence of nominal operating frequency limits given the constant magnetization curve of the vacuum. There is therefore no possibility that the core will saturate or even that vibrations will be established.

The so-called "in air" core therefore excludes all these problems and this is an advantage especially when dealing with highly distorted waveforms.

Air reactors are characterized by the following data:

  • Rated reactive power
  • Nominal phase inductance
  • Current rating
  • Frequency
  • Insulation class
  • Temperature class
  • Operating Ambient Temperature

 

The applications in which air reactors are used are many:

  • Filter reactors (harmonic filters, associated with condensers) 
  • Flattening reactors (reactors introduced to reduce/attenuate harmonics after AC/DC converters)
  • Shunt ballasts (for capacitive current compensation)
  • Inductive loads for test room


To complete the installation package, it is possible to introduce a central magnetic shunt into the circuit that can reduce the size of the reactance, while maintaining the performance for frequencies close to the mains frequency.