Motorola MBX Series Installation And Use Manual page 104

Specifications
A
A-4
and 490 LFM flowing over the module. Less airflow is required to cool the
module in environments having lower maximum ambient temperature.
Under more favorable thermal conditions, it may be possible to operate the
module reliably at higher than 70° C with increased airflow. It is important
to note that there are several factors, in addition to the rated CFM of the air
mover, which determine the actual volume and speed of air flowing over a
module.
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