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| Should as time progresses our supply become unstable and subject to sags and dips of the voltage levels, the two methods will react differently to the situation dependant upon severity. The fixed ratio transformer as the name suggests will always set the output to a fixed reduction depending on its setting (Fig. 5). |
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However, the regulator will always correct to its setpoint voltage as long as the input is within its correction range (Fig. 6). The Regulator correction range is determined from the unit setpoint value to a fixed percentage above to give the stated
reduction. Should the input fall below the regulator lower correction range limit (Fig. 6) then the output will adjust to this lower level and the site would be no worse off than if the regulator was not fitted. An example, would be if the regulator output is set at 220V P-N, then the input falls to 219V, so will the regulator’s output. However, should the input exceed the upper limit then the output voltage would be reduce to the maximum percentage reduction that the regulator is capable. |
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| It is possible that some site even now suffer ongoing disruptive voltage sags and dips, in this case we would suggest a voltage stabiliser is fitted. Unlike the regulator the stabiliser (Fig.7) has both a positive and negative (relative to setpoint) correction range. Voltage stabilisers have been used throughout the world but mainly in countries where the network infrastructure is poor and the supply inherently unstable. Although the basic design goes back fifty years there are constant refinements to continuously increase the reliability and to date there is no better way of high power control. |
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| Figure 5 |
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| Figure 6 |
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| Figure 7 |
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