Power Supplies - Compaq AlphaServer DS20E Reference Manual

Power Supplies

The system comes standard with two 375 watt power supplies that are connected
in parallel and can accommodate a third power supply, for redundancy. A
power backplane integrates the three supplies for power distribution, monitoring
and control. All three supplies are removable and accessible through the front of
the enclosure. The following voltages are provided: +3.3, +5.0, +12.0, –12.0,
+5.0 Aux, and fan power, with the +5 Aux always powered. Voltages, fans, and
thermals are monitored for safety by the I 2 C bus interface. Two internal fans
with a linear fan speed control ramp cool the power supply. Figure 1-9 shows
the power supplies.
Figure 1-9. Power Supplies
NOTE: With two power supplies, a power supply blank is needed to maintain the proper
air flow.
Compaq Confidential – Need to Know Required
Writer: Robert Young Project: DS20E Reference Guide Comments:
Part Number: ER-K8F6W-UA .A01 File Name: b-ch1 System Overview.doc Last Saved On: 10/4/99 1:23 PM
CAT0043
System Overview 1-19