ETC CEM3, Руководство пользователя

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System Reference 11
Variable Speed Fan (ESR Series Racks Only)
The variable speed fan reduces the amount of noise generated by a Sensor3 rack, specifically when the
rack is lightly loaded. The variable speed fan (where available) is supported in the following product
models:
• ESR24
• ESR36
• ESR48
The fan operates at two speeds: High and Low. The fan uses the AF Features of the rack to run more
slowly when less current is being drawn.
Operation in an Advanced Features Rack
In an Advanced Features (AF) rack, the modules are equipped with current feedback. The processor
uses the feedback data from the modules to determine the speed to run the fan.
If all modules have a measured current of 10 amperes or below, the fan will run in low speed mode. If
the current rises above the 10A threshold, the fan will increase to the higher speed.
If the rack or any modules have errors that might lead to increased heat, including the loss of
communication to AF cards, module over-temperature warnings, or ambient over temperature, the fan
will run in the higher speed mode.
Operation in a Non-Advanced Features Rack
In a non-AF rack, the fan speed is determined by the modules in the rack. If all modules are of a 10A
or below rating (e.g., all ED10 or below), the fan will run at the lower speed. The presence of any
higher current modules will cause the fan to run at higher speed.
Menu Structure
This section describes the menu structure of the software. Press the desired button to access the menu
items below. Use the standard navigation method to select and enter options in the menus (see
Navigation
on
page 3
).