Compaq AlphaServer GS60E Service Manual page 43

The system must be provided with a suitable source of 3-phase AC power.
Three H7506 power supplies (see Figure 2-7) provide the necessary power and
power redundancy required for all internal system components.
The AC input box is located at the bottom of the system cabinet (when viewing
the system cabinet from the rear). The 48 VDC power supplies are located
above the AC input box and are visible when viewing the system cabinet from
the front.
The AC input box provides the interface for the system to the AC utility power.
The DC distribution module connects the AC input box and power supplies. It
distributes the 48 VDC power. The circuit breaker and power indicators are at
the rear of the cabinet.
Circuit Breaker
The main circuit breaker, CB1, controls power to the entire system, including
the power supplies, blowers, and in-cabinet options. Current overload causes
the breaker to trip to the Off position, so that power to the system is turned off.
For normal operation, circuit breaker CB1 must be in the On position, with the
handle pushed up. To shut the circuit breaker off, push the handle down. Sub-
breakers CB2 through CB11 should also be in the On (up) position during
normal system operation.
AC Power Indicators
Three lights above the AC power line cord (see Figure 2-7) indicate that AC
power is supplied to the line side of main circuit breaker CB1.
The power supplies have two LEDs that indicate normal conditions and faults.
When the system (keyswitch) is off, plugged in, and the circuit breakers are on,
power is present only within the AC box and power supplies. The green VAUX
LEDs on the power supplies should be illuminated. When the system is on, the
VAUX and 48V LEDs should light.
Troubleshooting with LEDs 2-13