Why there is 3 phase mains input for this AC/DC power supply

power supply

Here is the specs:
http://www.linmot.com/fileadmin/doc/Accessories_Controller/ps_S01-72-1000_e_recent.pdf

This power supply outputs adjustable DC. But why it has 3 line inputs and an earth??

Best Answer

1kW is a high enough load that the balanced 3-phase circuit is an advantage.

Another advantage is that the filter capacitors need be much smaller for 3-phase, since a the output of a full-wave 3-phase bridge has less than 15% p-p ripple without any filtering at all. That would generally mean lower cost and longer MTBF for the power supply.