CAUTION:
If a third-party rack is used, observe the following additional requirements to ensure
adequate airflow and to prevent damage to the equipment:
• Front and rear doors—If the 42U rack includes closing front and rear doors, you must allow
5,350 sq cm (830 sq in) of holes evenly distributed from top to bottom to permit adequate airflow
(equivalent to the required 64 percent open area for ventilation).
• Side—The clearance between the installed rack component and the side panels of the rack must
be a minimum of 7 cm (2.75 in).
Temperature requirements
To ensure continued safe and reliable equipment operation, install or position the rack in a well-ventilated,
climate-controlled environment.
The operating temperature inside the rack is always higher than the room temperature and is dependent
on the configuration of equipment in the rack. Check the TMRA for each piece of equipment before
installation.
CAUTION:
To reduce the risk of damage to the equipment when installing third-party options:
• Do not permit optional equipment to impede airflow around the chassis or to increase the internal
rack temperature beyond the maximum allowable limits.
• Do not exceed the manufacturer’s TMRA.
Grounding requirements
• The building installation must provide a means of connection to protective earth.
• The equipment must be connected to that means of connection.
• A service person must check whether the socket-outlet from which the equipment is to be powered
provides a connection to the building protective earth. If the outlet does not provide a connection, the
service person must arrange for the installation of a protective earthing conductor from the separate
protective earthing terminal to the protective earth wire in the building.
Connecting a DC power cable to a DC power source
WARNING:
To reduce the risk of electric shock or energy hazards:
• This equipment must be installed by trained service personnel, as defined by the NEC and IEC
60950-1, Second Edition, the standard for Safety of Information Technology Equipment.
• Connect the equipment to a reliably grounded Secondary circuit source. A Secondary circuit has
no direct connection to a Primary circuit and derives its power from a transformer, converter, or
equivalent isolation device.
• The branch circuit overcurrent protection must be rated 20 A.
WARNING:
When installing a DC power supply, the ground wire must be connected before the
positive or negative leads.
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Temperature requirements
