User Guide
1. Overview
1.2 System Architecture Overview
The following image displays the thermal zones as viewed from the top of the enclosure. When viewing
the enclosure from the front, the right device zone is on the right-hand side and the left device zone is
on the left-hand side. When viewing the enclosure from the rear, the order is reversed. Each of the two
thermal zones contains major components that are thermally maintained within their specific zone.
Figure 3:
System Thermal Zones
The E3000 uses a base algorithm, called a thermal algorithm, to control the overall thermal environment of
the system. The system is mechanically separated into two thermal zones to support efficient cooling of
the system components in order to achieve the intended performance of the system. The thermal zones
are split into device zones (the left and right side of the enclosure) and center zone when standing at the
front of the system. The device thermal zones contain up to ten devices or device blanks each that are
cooled by four fan modules that are located directly behind the devices. The four fan modules behind the
devices maintain the cooling for devices contained within the device slot installed into A through J. The
center thermal zone contains the BMC module that is cooled by the fans contained in the redundant PSUs
the are located directly behind the BMC module. The different thermal zones are designed to maintain
proper thermal cooling across the entire system. During servicing the system increases the speed of the
fan modules and PSU fans to maintain a balanced thermal load.
1.2.2.1
System Thermal Algorithm
The System Thermal Algorithm is designed to use temperature sensors and defined thresholds to
determine if the algorithm will select critical, increase, decrease, or no change as the device decision.
The System Thermal Algorithm uses the concept of priorities to ensure the proper function of the system.
As a result, any critical fault results in the system ramping the fans to maximum RPMs to protect the
hardware for the duration of the fault. The fault will remain in a critical state until the fault is fully resolved
and by bringing the temperature back within the specified defined thresholds.
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