Fan Speed Control; Power Supply Module Fan; Table 21: Pwm Settings; Table 22: Temperature Notification Thresholds - Intel JBOD2312S3SP Hardware Manual

5.5 Fan Speed Control

Fan speed control for this system is driven primarily by the front panel temp sensor which is representative
of system ambient Temperature (Tsa). Fan speed override is driven by thermal sensors located on the
expander board.
The thermal solution in this 2U system utilizes four 60mm x 38mm fans.
The FSC algorithm includes a 4 data point rolling average to assert the threshold value and 2ºC hysteresis to
prevent fan speed oscillations.
Actual sensor temperature is -20ºC – SES protocol uses a 20ºC offset.

Front Panel Sensor 1 has a 2ºC offset due to self-heating.

Fan control overrides:
If Temperature Sensor 3 exceeds its High Warning threshold -> set Fans to 80%.

If Temperature Sensor 3 exceeds its High Critical threshold -> set Fans to 100%.


5.6 Power Supply Module Fan

Each installed power supply module includes one embedded (non-removable) 40-mm fan. It is responsible
for airflow through the power supply module. If this fan fails, the power supply will continue to operate until
its internal temperature reaches an upper critical limit. The power supply will be protected against over
temperature conditions caused by loss of fan cooling or excessive ambient temperature. In an over-
temperature protection condition, the power supply module will shut down.
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Intel® Storage Server System JBOD2312S3SP Hardware Guide

Table 21: PWM Settings

Altitude
Tsa[C]
11C
25C
28C
30C
33C
35C
40C
43C

Table 22: Temperature Notification Thresholds

Limit
High Critical 56C
High Warning 54C
Low Warning 27C
Low Critical 22C
Up to 3000M
Fan Failed
PWM
45%
45%
50%
55%
100%
60%
65%
80%
100%
Sensor1 Sensor 3 – Expander
Front Panel Processor Internal
125
120
25
20