In this case, the Elektro-Automatik Autoranging supply is rated at just half the power of the legacy square supply, yet provides more current and allows ample headroom, even the DVT case down to 180 Vdc.
In general, power supplies are $ X / watt. The higher the power, the higher the cost. An autoranging power supply could be as much as half the cost of the legacy supply.
One thing to consider when selecting an autoranging power supply is to plan for the future or leverage into other applications. What if instead of 400 Vdc, the input voltage increased to say 600 Vdc? Why not use a 750 Vdc source?
The PSI 9750-20 3U is again rated at 5,000 W and provides 750 Vdc and up to 20 Adc. The source still meets application requirements, yet offers the benefit of higher voltage output. In the autoranging diagram, that’s the “Extra Range”.