About Dc Power Supply Units; Power Indicator Codes - Dell MD1420 Hardware Owner's Manual

Figure 14. Securing the power cable
a. Velcro strap
CAUTION: When connecting the power cable, secure the cable with the Velcro strap.
NOTE: If the enclosure is powered on, all the power supply LEDs remain off until the AC power cable is connected to
the power supply unit or cooling fan module and the power switch is turned on.
4. Turn on the power supply unit or cooling fan module.

About DC power supply units

An MD Series storage array receives its power from two power supply modules. In a DC-powered MD Series storage array, the power
supply module receives power from two 48 V DC PSUs. Each power supply module has two cooling fans.
NOTE: The fans that keep the array cool are integrated into the power supply modules and cannot be replaced
separately. If a fan stops functioning, you must replace the entire power supply module.

Power indicator codes

The DC power supply module has LEDs that indicate power supply status. Under normal conditions, the power output and line input LEDs
are lit at the same time.
Figure 15. Power indicator codes
18 Installing enclosure components