CIRCUTOR computer SMART Series (Available until stock) - Manual (Page 7)

M98235701-03-12A Computer Smart 6/Computer Smart 12
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1.2.6 Connection and Reconnection Time.
Connection time Tc defines the minimum time between changes in the status of stages, i.e., between
connections and disconnections. Therefore, the configuration of this parameter has a direct impact on the
compensation speed, in other words, on the monitoring capacity after changes in load. Establish a shorter
connection time to improve the power factor correction when the load can change quickly.
However, a shorter Tc will lead to a higher number of connections per time unit, shortening the useful life of
the associated components (contacts, capacitors). To assess the number of connections, Computer Smart
uses individual meters for each capacitor.
The reconnection time is the minimum time between the disconnection of a stage and its reconnection. This
time is required to discharge the capacitor enough to prevent an over-current in the system after it is
reconnected.
1.2.7 Harmonics and THD
Non-linear loads, such as those in rectifiers, inverters, speed drives, kilns, etc., absorb non-sinusoidal
periodic currents from the grid. These currents are composed of a fundamental frequency component, rated
at 50 or 60 Hz, plus a series of overlapping currents, with frequencies that are multiples of the fundamental
frequency; they are defined as harmonics. The result is a deformation of the current and, as a consequence,
of the voltage, which leads to a series of associated secondary effects (overloads in conductors, machines
and automatic switches, phase offsets, interferences in electronic equipment, RCCB trips, etc.).
The level of harmonics is usually measured with the total harmonic distortion rate (THD), which is the ratio,
usually as a %, of the RMS value of the harmonic content and the value of the fundamental component.