Technical data

Dual 9-, 12-, and 20-Slot Power Supply
7-7
7
AC/DC Power Supply Operation
When one each of an AC input and a DC input supply are installed together, they
operate with the following characteristics.
1). When adding the second power supply to the system, AC or DC, it can be plugged
into a backplane of a running system before the input power cord is attached and not
cause the running power supply to fault.
2). When one of each of an AC input and a DC input supply are installed in a system,
and each has appropriate input power and is enabled, the AC input supply operates
and provides 100 percent of the output load, and the DC input supply is in standby
mode, providing no output power.
3). If input power is then removed from the AC input supply, the DC input supply exits
standby mode and enters operating mode, and provides 100 percent of the output
loads. If input power is subsequently re-applied to the AC input supply, it starts and
again provides 100 percent of the output load. The DC input supply simultaneously
exits operating mode and enters standby mode, providing no output power. These
conditions do not cause an output voltage fault.
4). If input power is instead removed from the DC input supply, the AC input supply
continues operating normally, and this does not cause an output voltage fault.
Remote Sensing
Remote sensing of output #1 load is able to automatically compensate for a voltage drop
of 0.25 Vdc minimum. If parallel supplies both - sense wires tied to common.
Overshoot
Overshoot does not exceed 2.0% of any output voltage, power failure, enabled,
disabled, and AC input cycle on or off.
Load Change Transient Response
Any DC voltage returns to 1% within 2 mS in response to a 25% load step. Any DC
output does not vary more than 3% in response to a 25% load step.
Undershoot/Reverse Voltage
With respect to its normal zero reference voltage, no output voltage does, under any
normal condition become a polarity opposite to its normal operation polarity.
(Excluding applying an external reverse voltage.)
Table 7-3. 700 Watt AC Power Supply Specifications (Continued)