Brocade Communications Systems 53-1002599-01 Manuale Utente

Replacing a power supply unit

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You can use external labels as a guide. The power supplies and fan assemblies are labeled with an 
airflow symbol on the faceplate to indicate whether the assembly takes in or exhausts air. The 
symbol also appears on the top of the FRU. All FRUs in a chassis must have the same label affixed 
so that airflow direction is consistent. 

 illustrates examples of the airflow labels.

FIGURE 18

Examples of airflow symbols

The green E symbol indicates an exhaust FRU. This unit pulls air in from the front of the switch and 
exhausts it out the rear side. This is called front-to-back airflow or forward airflow. 

The orange I symbol indicates an intake FRU. This unit pulls air in from the rear side of the switch 
and exhausts it out the front side. This is called back-to-front airflow or reverse airflow. 

The show chas command displays a device’s airflow direction: Front-to-Back or Back-to-Front.

Replacing a power supply unit

CAUTION

Remove the power cord from a power supply before you install it in or remove it from the device. 
Otherwise, the power supply or the device could be damaged as a result. (The device can be 
running while a power supply is being installed or removed, but the power supply itself should not 
be connected to a power source.)

CAUTION

For the Brocade ICX 6650 devices, be sure that the airflow direction of the power supply unit 
matches that of the installed fan tray. The power supplies and fan trays are clearly labeled with 
either a green arrow with an “E”, or an orange arrow with an “I.”

ATTENTION
Maintain all power supply and fan assemblies in operational condition to provide redundancy.

CAUTION

Because the cooling system relies on pressurized air, do not leave any of the power supply and 
fan assembly slots empty longer than two minutes while the switch is operating. If a power supply 
or fan assembly fails, leave it in the switch until it can be replaced.

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