IBM DS3200 Storage Subsystem Heat output, airflow, and cooling

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

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

system.

After normal power is restored after a total ac power failure, the storage subsystem

performs power-on recovery procedures automatically without operator intervention.

The storage subsystem comes with two jumper cords that are used to connect to

the rack PDU. Youmust 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 11shows 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.

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. Toprevent 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).

System Storage

Airflow

Figure11. DS3200 airflow

Chapter1. Introduction 15