SMART Embedded Computing 6806800V18A, Installation And Use Manual

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146 AXP1440-C07 Installation and Use (6806800V18A)
Shelf Management Module
Shelf Management Module
7.4 Management and Control
This section gives a general description of the role of the on-board I
2
C devices and how
management, control, and redundancy is handled by the SAM1620-D. Detailed information
on sensors can be found in the
Centellis 4440/4620 Control via IPMI Programmer’s
Reference
manual.
7.4.1 Hardware Monitoring and Control
The hardware monitoring and control functions implemented by the AXP1440-C07 are
provided by the on-board I
2
C-based devices.
7.4.1.1 Voltage Sensors
On-board sensors provide the following power supply voltages. All voltage sensors are
implemented using the ADM1024 device on the master-only I
2
C bus. System management
software running on the SAM1620-D is responsible for reacting to an event when an
interrupt is triggered by the ADM1024 device.
7.4.1.2 Temperature Monitoring
An on-board temperature sensor is available on the SAM1620-D. This sensor is
implemented through the ADM1024.
7.4.1.3 Fan Speed and Control
All fan speed and fan voltage sensors are exposed on the active SAM1620-D.
The fan tray modules have 110 fan speed settings. The SAM1620-D uses a proprietary
cooling algorithm to automatically adjust the fan speed to cool the chassis based on sensor
data from the blades as well as inlet and outlet sensors on the s. The minimum fan speed
is 1.
In normal operating conditions, the cooling algorithm adjusts the fan speed based on the
ambient air temperature as measured at the inlet fans to maintain a
deltaT value
(calculated to be the rise in air temperature measured at the inlet and outlet fan sensors)
based on the inlet air temperature value. The lower the ambient temperature, the higher the
rise in temperature allowed.
At least one shelf manager must be in the shelf for proper operation of the cooling
algorithm. Removal of both shelf managers will result in the fan speed remaining the
same and uncontrolled.