A substation may contain hundreds of transformers. The measured voltages and currents are scaled so that the +/-5V or +/-10V full-scale output range of the transformers represents a range much greater than the full-scale power output capability of the power line. Generally, the power line, especially the current measurements, will run at less than 5% of this range, and typical transformer outputs will lie in a +/-20mV range. Larger signals occur rarely and when they do, they usually imply a system fault. Accurate measurement of these small signals requires a high-resolution ADC with excellent signal to noise ratio (S/N). The dynamic range is the key for this application. Currently, 16 bit resolution requirements provide wide dynamic range and capture surges, transients, etc. However, 16 bit accuracy is only required within the ‘normal range’, not over a wider dynamic range and often 16 bits is not required in normal operation.