Bosch Appliances Computer Hardware DVA-08K User Manual

en | Introduction

RAID Subsystem DVA-08K | Installation Manual

F.01U.027.797 | V2 | 2008.08

Bosch Security Systems

Top View of a Cooling Fan Module

The cooling fan modules support dual-speed operation modes that help to protect the subsys-

tem in the event of component failure or extreme working condition.  

The cooling fans operate with two rotation speeds. Under normal operating conditions, the 

cooling fans run at the low speed, which is sufficient for maintaining efficient airflow across 

components. Under the following conditions, cooling fans raise their rotation speed to 

increase the airflow:

1.

Component Failure: if another cooling fan module, a PSU, or a temperature sensor fails, 

the remaining cooling fan(s) automatically raises its rotation speed.

2.

Elevated Temperature: if the temperature breaches the upper threshold set for any of the 

interior temperature sensors, the cooling fans automatically raises its rotation speed.

3.

During the subsystem initialization stage, the cooling fans operate at the high speed and 

return to lower speed once the initialization process is completed and no erroneous con-

dition is detected.

There are two values set for the upper temperature thresholds. One is set for event notifica-

tion and the other triggering higher fan rotation speed. The preset value for event notification 

can be changed using the firmware-embedded configuration utility, while the fan speed trig-

ger is not a user’s option.