The agency ratings for the DS3200 storage subsystem are 6 amps at 100 V ac and

2.5amps at 240 V ac. These are the overall maximum operating currents for this system.

AC power recovery

After normal power is restored after a total ac power failure, the storage subsystem performs power-on recovery procedures automatically without operator intervention.

Power cords and receptacles

The storage subsystem comes with two jumper cords that are used to connect to the rack PDU. You must purchase the power cords that are applicable for use in a typical receptacle in your country. See “Power cords” on page 106 for more information.

Heat output, airflow, and cooling

Figure 11 shows the intended airflow for the DS3200. Allow at least 30 inches in front of the storage subsystem and at least 24 inches behind the storage subsystem for service clearance, proper ventilation, and heat dissipation.

Figure 11. DS3200 airflow

When racks that contain many DS3200 storage subsystems are to be installed together, the following requirements must be met to ensure that the DS3200 storage subsystems are adequately cooled:

vAir enters at the front of the rack and leaves at the back. To prevent the air that is leaving the rack from entering the intake of another piece of equipment, you must position the racks in alternate rows, back-to-back and front-to-front. This arrangement is known as “cold aisle/hot aisle” and is shown in Figure 12 on page 16.

vWhere racks are in rows, each rack must touch the rack that is next to it to reduce the amount of hot air that can flow around from the back of the rack into the intakes of the storage expansion enclosures that are in that rack. Use Suite Attach Kits to completely seal any gaps that remain between the racks. For details about Suite Attach Kits, contact your IBM marketing representative or authorized reseller.

vWhere racks are in rows front-to-front or back-to-back, gaps of at least 122 cm (48 in.) must separate the rows across the cold aisle (see Figure 12 on page 16).

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IBM DS3200 Storage Subsystem manual Heat output, airflow, and cooling, AC power recovery