Percent deviation above or below the nominal (or rated) output voltage when the incoming voltage is within the input range.
In other words, this is a measure of how accurate or tight the output
voltage will be. Smaller numbers mean more precise regulation. An
output regulation of ±3% is well within the tolerance required by the
vast majority of electric devices. For special applications such as
laboratory testing or calibration, an output regulation of ±1.5% or
less may be more desirable. For a nominal 208v output, ±3% output
regulation equals 214v to 202v. With many voltage regulators,
there will be a direct correlation between the input range and the
output regulation. As the output regulation becomes smaller, the input
range will also shrink. This is due to the fact that manufacturers will
have a fixed number of points or taps at which changes in output
voltage can be made. To decrease the output regulation percentage
without decreasing the input range requires that more taps be added.
This becomes a custom and more expensive design. |