Figure 184: Mts 2 Airflow - Motorola DIMETRA MTS 4 Installation, Configuration, And Service Manual

Applicant: Motorola Solutions
308 | Cooling Fans

Figure 184: MTS 2 Airflow

MTS 4:
In MTS 4 the airflow is different. The additional depth and width of the cabinet are used to guide and separate
ambient air intake and heated air outlet. For both card cages the main airflow of ambient air enters at the front. At the
bottom card cage the air can enter from all sides. For the top card cage the air has to pass in front of and behind the
bottom card cage. In the front, between the modules and the cabinet door. In the back, between the bottom card cage
back and the back of the cabinet. The flow is obstructed by an insert which guides the hot air from the bottom card
cage out to the sides and up between the top card cage and the cabinet sides. The exhaust from the top card cage could
be partly obstructed by a Cavity Combiner situated above. The exhaust can occur on all sides. No obstructions are
inserted. Due to the obstructions in the airflow, fans are required for all configurations of MTS 4.
The fans have a low rpm alarm indication. Each fan module (part no. WALN4381) has two fans inside. In case of
failure, one of the fans still gives an airflow. Therefore the fan module is not considered a periodic maintenance
component, but is only replaced when it fails.
Send Feedback | September 2014 | 6802800U74-AD
Equipment Type: ABZ89FC5827 / 109AB-5827
Exhibit D2