Multiple Pcms; System Airflow; Power Supply Unit (Psu) - Lenovo Storage D1212 Hardware Installation And Maintenance Manual

If all LEDs are amber and flashing, it indicates that a PCM firmware update is in progress.
If the DC Output Fail is On, it indicates that a PCM detected DC output fail or firmware detected fault.
PCM LEDs are shown in the following figure.
Figure 24. 580W PCM LEDs

Multiple PCMs

The 2U system includes two PCMs which provide redundant power control for the system so that if one PCM
fails the other maintains the power supply and enclosure operation is not affected while you replace the
faulty module.
PCMs are hot-pluggable and replacement should only take a few seconds to do. Replacement must be
completed as soon as possible after the removal of the defective PCM to avoid a thermal exception, and
within an absolute maximum of 2 minutes.
Important: Operation of the enclosure with ANY modules missing disrupts the airflow and the drives could
not receive sufficient cooling. It is ESSENTIAL that all bays are fitted with PCMs or PCM blanks prior to
switching on the enclosure.

System Airflow

The system must be operated with low-pressure rear exhaust installation. Back pressure created by rack
doors and obstacles is not to exceed 5 pascals (0.5 mm water gauge). The cooling system provides sufficient
capacity to ensure that maximum temperatures are not exceeded.
Important: The environment in which the enclosure operates must be dust-free to ensure adequate airflow.

Power Supply Unit (PSU)

Note: 5U Enclosures only.
Power is provided by two 2214W PSUs, as shown in Figure 25 "2214W PSU" on page 23. It requires an input
of 200VAC to 240VAC at 50 Hz to 60 Hz.
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Lenovo Storage D1212/D1224/D3284Hardware Installation and Maintenance Guide