Compaq AlphaServer GS60 Operation Manual page 41

The power regulator is located in the lower third of the cabinet. The CCL panel is
located in the processor system unit (PSU), next to the control panel.
The system can have up to two power regulators. In this configuration an optional
power strip is installed at the rear of the cabinet so that only one AC input connection
is required. In a dual power supply system the regulators are used in parallel, one for
the required load plus an additional power regulator for backup in case of failure.
Each power regulator has an AC input assembly, a 48 VDC power regulator, two
cooling fans, indicator lights, and optional battery backup (charger module and battery
packs for UPS operation).
Each power regulator has a circuit breaker; access is from the rear of the cabinet.
AlphaServer 8200 System 2-17