IBM DCS9550 1S1 Manuale Utente

Troubleshooting and Problem Solving

IBM System Storage DCS9550 1S1 Storage Expansion Unit Installation, Service, and User Guide

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The DCS9550 1S1 Storage Expansion Unit uses extensive thermal monitoring and takes a 

number of actions to ensure component temperatures are kept low and also to minimize 

acoustic noise. Air flow is from front to rear of the enclosure.

If the ambient air is 
cool (below 25 °C) and 
the fans are observed 
to increase in speed 
then some restriction 
on airflow may be 
causing additional 
internal temperature 
rise.
Note: This is not a fault 
condition.

The first stage in the 
thermal control process 
is for the fans to 
automatically increase 
in speed when a 
thermal threshold is 
reached. This may be 
caused by higher 
ambient temperatures 
in the local environment 
and may be perfectly 
normal.
Note: This threshold 
changes according to 
the number of drives 
and power supplies 
fitted.

1 Check the installation for any airflow 

restrictions at either the front or rear 

of the enclosure. A minimum gap of 
25mm at the front and 50mm at the 
rear is recommended. 

2 Check for restrictions due to dust 

build-up; clean as appropriate.

3 Check for excessive re-circulation of 

heated air from rear to the front, use 
in a fully enclosed rack installation is 
not recommended. 

4 Check that all Blank modules are in 

place.

5 Reduce the ambient temperature.