CAUTION: DO NOT mix airflow directions. The airflow directions are color coded. A
red label indicates that hot air is expelled from the PSU and a blue label indicates
that hot air is expelled from the I/O. Both fans must use the same airflow direction
(I/O to Utility or Utility to I/O). The power supplies and fans must have the same
color strap. If you mismatch the airflows, the following error message appears and
the system shuts down:
00:02:19: %S5000:0 %CHMGR-2-PSU_TYPE_AIRFLOW_MISMATCH:
Mismatching PSU airflow detected. Unit 0 shall get
shutdown in next 60 seconds if mismatch not rectified.
00:02:19: %STKUNIT0-M:CP %CHMGR-1-
PSU_AIRFLOW_COMBO_MISMATCH: Major alarm: Mismatching
PSU airflow detected in unit 0
Installing a DC Power Supply
1.
Remove the PSU from the electro-static bag.
2.
Use the grab handle to slide the PSU into the switch PSU slot (install the PSU-
exposed PCB edge connector first). The PSU slot is keyed so that the PSU can be
fully inserted in only one way. When you correctly install the PSU, it snaps into
place and is flush with the back of the switch.
Figure 18. Installing a DC Power Supply
1. Slot 0 (for DC PSU 0)
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