The I.S. System Power Supply accepts locally available 24 VDC (nominal) power and converts it to 12 VDC for powering I.S. I/O cards. Each I.S. power supply is rated at 5 A and can power from eight to fifteen cards depending upon the type and mix of cards. You can have up to ten I.S. power supplies and add an additional power supply for redundancy. (The total number of I.S. power supplies for a redundant system is eleven.) When using multiple I.S. system power supplies, intersperse the power supplies among the cards.
The I.S. Power Supply supplies 60 W and draws 80 W for 24 VDC bulk power supply calculations at the rated load.