80 Installation TB8100 Installation and Operation Manual
© Tait Electronics Limited June 2005
To allow enough cooling airflow through a cabinet-mounted BSS, we 
recommend the following:
■ an area of at least 150cm
2
 (23in
2
) of unrestricted ventilation slots or holes 
in front of the air intakes for the fans for each subrack;  for example, 
thirty 6x85mm (0.25x3.3in) slots will allow the recommended airflow
■ a vent in the top of the cabinet with an area of approximately 150cm
2
 
(23in
2
) per subrack, or a similar area of ventilation per subrack at the rear 
of the cabinet behind each subrack
■ a 2U gap at the top of the cabinet.
Note The ventilation opening must be unrestricted.  If the slots or holes 
are covered with a filter, mesh or grille, the open area must be 
increased to allow the same airflow as an unrestricted opening.
The maximum ambient temperature entering the cabinet must not exceed 
+60°C (+140°F).
If the TB8100 BSS is installed in a rack or cabinet with other equipment 
with different ventilation requirements, we recommend that the TB8100 be 
positioned below this equipment.  
Auxiliary Extractor 
Fans
The TB8100 BSS does not require auxiliary extractor fans mounted in the 
top of the cabinet.  If your cabinet is already fitted with fans, the following 
procedures apply:
■ if there are six or more 120mm (4.75in) fans, each capable of extracting 
160m
3
 per hour (94.2CFM), they must run continuously
■ if there are fewer than six fans, you must remove them and ensure the 
vent in the top of the cabinet has an area of approximately 150cm
2
 
(23in
2
) per subrack.
If you have any other configuration, the performance of your system will 
depend on how closely you comply with the TB8100 BSS airflow 
requirements described above.