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Figure 4. IBM SAN48C-6 Fan Module
To facilitate different data center cooling configurations of hot or cold aisles and racks, there are two
models of fan modules. The first type has airflow with port-side intake and exhaust at the rear of the
chassis. The second type has airflow in the opposite direction, that is, rear-chassis intake and port-side
exhaust. The airflow direction is denoted on each fan module as follows:
• Red—Port-side intake airflow
• Blue—Port-side exhaust airflow
For more information on installing and removing fan modules, see Installing and Removing Fan Modules.
Power Supplies
The IBM SAN48C-6 Switch PSUs have an unswitched power receptacle, a PSU status LED and a handle for
insertion and removal of the PSU from the chassis. The IBM SAN48C-6 Switch requires a minimum of one
operating PSU. It supports up to two PSUs. This provides redundancy for uninterrupted operation in the
event of PSU or grid failure. The PSUs are hot-swappable to allow swapping out of a PSU during operation
for uninterrupted operation. During a PSU replacement, the internal airflow through the chassis is
changed. If the internal airflow is disrupted for too long, the preset temperature thresholds will be
exceeded and the system will automatically shut down to prevent permanent damage.
Figure 5. IBM SAN48C-6 PSU
To facilitate different data center cooling configurations of hot or cold aisles and racks, there are two
models of PSUs. The first type has airflow with port-side intake and exhaust at the rear of the chassis. The
second type has airflow in the opposite direction, that is, rear-chassis intake and port-side exhaust. The
airflow direction is denoted on each PSU as follows:
4 IBM Storage Networking: IBM Storage Networking SAN48C-6 32 Gbps 48-Port Fibre Channel Switch
Installation, Service, and User Guide