Advanced Power System (APS) N6900 Series supports 4 performance options. While Option 301 adds second measurement range for current (with full factory calibration), Option 302 adds external data logging as well as voltage and current digitizers with programmable sample rates. Option 303 adds constant-dwell arbitrary waveforms and output list capability, while disconnect and polarity-reversal relays (Options 760 and 761) let engineers switch voltages between positive and negative values.