The concept of a redundant power supply is that the individual power supply units back each other up incase one of them fails. The power supply units are also hot swappable. This means if one goes bad, you do not have to shut down the system to replace it. You simply unlock the bad power supply and replace it with a good one. The computer you are performing this operation on never has to be shut down or rebooted, which helps you maintain a 100% uptime with your server.
 

     So how do you know if one unit goes bad? I-Star makes this simple. Each unit has its own LED on the back side of the PSU as well as a set of external LEDs. If the LED is on steady, the PSU is good. If the LED is flashing, the PSU is bad. The set of three external LEDs have plenty of wire so you can install them on the front of the case or even on a separate panel outside of the box. These LEDs also monitor each PSU with the third being a master power LED. There is also an audible alarm that sounds when one PSU is off or goes bad.

     When it comes to power cables, this PSU is strictly for servers and multi CPU workstations. WARNING: This PSU will not work with a standard ATX motherboard without a main power connecter adapter. Besides the main power connector, there is a +12v 8-pin power connector AND a +12v 4-pin power connector. Looking for plenty of 4-pin power connectors for your devices? This PSU has a total of 7, not counting the single floppy drive power connector.