An OptiX OSN 9800 M12 subrack contains one fan tray assembly, which has four dual-fan conjoined modules. There is an air filter at the bottom of the OptiX OSN 9800 M12 subrack. The air filter can be directly removed for cleaning.

The fan tray assembly is located in the upper part of an OptiX OSN 9800 M12 subrack. It draws external air into the subrack and dissipates heat by blowing air out of the subrack, forming an air duct from bottom to top.The boards in each section are inserted vertically so that the boards and the air duct are horizontal, ensuring reliable heat dissipation.

Source: https://support.huawei.com/hedex/hdx.do?lib=EDOC1100213669BEK09268&docid=EDOC1100213669&lang=en&v=02&tocLib=EDOC1100213669BEK09268&tocV=02&id=EN-US_CONCEPT_0157941274&tocURL=resources%252Fhelp%252Fwdm%252F9800%252Fhd%252Fothers%252Ffillerpnl_func.html&p=t&fe=1&ui=3&keyword=air%2Bflow

Heat Dissipation

The fan tray assembly is located in the upper part of an OptiX OSN 9800 M12
subrack. It draws external air into the subrack and dissipates heat by
blowing air out of the subrack, forming an air duct from bottom to
top.The boards in each section are inserted vertically so that the
boards and the air duct are horizontal, ensuring reliable heat
dissipation.

Figure 1 and Figure 2 show the schematic diagrams for heat dissipation of an OptiX OSN 9800 M12 subrack.

Figure 1 Heat dissipation when only one subrack is deployed inside the same cabinet

Figure 2 Multi-subrack OptiX OSN 9800 M12 subrack ventilation system

To
ensure a complete air duct for normal heat dissipation, boards or
filler panels must be inserted in vacant slots within 5 minutes, and a
new fan tray assembly must be inserted within 3 minutes after the original one is removed during fan tray assembly replacement.

If any fan in the fan tray assembly fails, the OptiX OSN 9800 M12
can remain operational for a short period of time (that is, continuous
operation for fewer than 96 hours or operation for fewer than 15 days in
a year) at a temperature ranging from 0°C to 40°C. To ensure long-term
and stable operating, you are advised to replace the fan tray assembly
as soon as possible.

Dear friend!

The fans of the OptiX OSN 9800 M12 usually work in automatically adjusting their speeds mode.

When the board temperature is within the specified range, the fans intelligently adjust their speeds to ensure stable heat dissipation for boards while ensuring low noise and energy consumption.

Therefore, its rotation speed is not fixed, so there is no such parameter.

Thank you!