For these desktop power supplies Power Solutions - AC-DC Power Supplies - Page 1 - Rfwel Engr E-Store, what would be the outcome connecting two identical units to double my voltage. Say two of the Samlex SEC-1223 (Samlex SEC-1223 23A Desktop Switching Power Supply - Rfwel Engr E-Store) to get 24VDC out and 23A out. 

I can also see the voltage output marked as 13.8VDC and not 12VDC? What's the implication?