•
Solid-walled cabinets with a roof fan tray (bottom to top cooling)
Installation clearance requirements for solid-wall cabinets are not in the scope of this
guide. Such installations have to be custom-engineered by a cooling professional. The
customised configuration should satisfy the requirements mentioned in the
and the
sections.
Note
•
Standard open four-post Telco racks
To correctly install the switch in a cabinet that is located in a hot-aisle/cold-aisle environment, you should fit
the cabinet with baffles to prevent exhaust air from recirculating into the chassis air intake.
Work with your cabinet vendors to determine which of their cabinets meet the following requirements or see
the Cisco Technical Assistance Center (TAC) for recommendations:
•
Use a standard 19-inch, four-post Electronic Industries Alliance (EIA) cabinet or rack with mounting
rails that conform to English universal hole spacing per section 1 of the ANSI/EIA-310-D-1992 standard.
•
The height of the rack or cabinet must accommodate the 26-RU (45.25 inches or 114.9 cm) height of
the switch and its bottom support bracket.
•
The depth of a four-post rack must be 24 to 32 inches (61.0 to 81.3 cm) between the front and rear
mounting brackets.
•
Required clearances between the chassis and the edges of its rack or the interior of its cabinet are as
follows:
◦
7.5 inches (19.1 cm) is required between the chassis and the front of the rack or interior of the
cabinet (required for cabling).
◦
3.0 inches (7.6 cm) is required between the rear of the chassis and the perforated rear door of the
cabinet (required for airflow inside the cabinet if used).
This requirement does not apply to enclosures which have a solid rear door or wall with
other exhaust configurations.
Note
◦
No clearance is required between the chassis and the sides of the rack or cabinet (no side airflow).
Additionally, you must consider the following site requirements for the rack:
•
Power receptacles must be located within reach of the power cords used with the switch.
◦
AC power supplies
◦
Power cords for 3-kW AC power supplies are 8 to 12 feet (2.5 to 3.6 m) long.
◦
DC power supplies
◦
Power cords for 3.0-kW DC power supplies are supplied and dimensioned by the customer.
◦
HVAC/HVDC power supplies
Cisco Nexus 7718 Switch Site Preparation and Hardware Installation Guide
OL-30453-01
15
Preparing the Site
Rack and Cabinet Requirements