Fan Speeds And Temperature Thresholds On The B16S - IBM s-series Installation And User Manual

High temperature threshold
Low temperature threshold
HIGH
High temperature threshold
Low temperature threshold
MEDIUM-HIGH
High temperature threshold
Low temperature threshold
MEDIUM
High temperature threshold
Low temperature threshold
MEDIUM-LOW
High temperature threshold
LOW
Figure 30. Fan speeds and temperature thresholds on the B16S
The low and high temperature thresholds enable the device to determine at which
speed the fans should operate. In general, the fans operate as follows:
v If the temperature of all thermal planes is between the low and high thresholds
for a fan speed, the fan continues to operate at that fan speed.
v If the temperature of any thermal plane exceeds the high threshold specified for
a fan speed, the fan speed increases to the next higher speed. If the temperature
of any thermal plane exceeds the high threshold for the high speed and remains
above the threshold for five minutes, the system automatically shuts down to
prevent damage.
v If the temperature of any thermal plane falls below the low threshold for a fan
speed, the fan decreases its speed to the next lower speed. If the temperature of
any thermal plane falls below the high threshold for the low speed, the fan
operates at the low speed.
If the temperature of any thermal plane exceeds the high temperature threshold for
any of the fan speeds, the software sends a message to the system log.
Table 19 on page 64 outlines the default low and high temperature thresholds for
each thermal plane and fan speed in the B16S.
Note: Table 19 on page 64 applies to the B16S only.
Chapter 5. Managing the Chassis and Modules
63