Keysight M9502A, User Manual, Page: 79 / 142

Keysight M9502A/M9505A AXIe Chassis User Guide 69
Shelf Management Functions Features and Functions
Under
Fan Control
, you can monitor Fan Status, Cooling Status, Present Fan Level,
and Minimum Fan Level. These are explained in order below.
Fan Status:
The shelf manager continuously monitors chassis fan speed,
looking for possible indication that one or more fans are not turning. Nominal fan
status represents a fan speed of approximately 2,000 RPM, higher when required
by instrumentation load. Below that range, the shelf manager will report an
alarm condition for that fan, attempt to increase fan speed and continue to
monitor. Failure of one fan will not result in interruption of power to installed
modules. The fan status conditions are listed below.
Cooling Status:
The shelf manager continuously monitors reported module
temperatures, looking for indication that one or more modules is outside its
optimal temperature range. This range is specified by the module vendor, as are
the thresholds for alarm conditions. Typically only high temperatures generate
an alarm, although it is possible for a vendor to specify low temperature alarm
levels as well.
In the event of a high temperature alarm from any module, the shelf manager will
respond by increasing chassis fan speed and continuing to monitor. If the Upper
Non-Recoverable level is reached, the shelf manager will shut down power to
that module. As this level is set by the module vendor, it may not indicate that
the module has failed, only that continued operation is inadvisable until the
module cools.
Fan Status Fan Speed (RPM) Shelf Manager Response
Nominal 2,000 or higher Continue monitoring fan speed
Lower Non-Critical Increase fan speed one step and continue monitoring
Lower Critical Increase fan speed to maximum and continue monitoring
Lower Non-Recoverable This usually indicates a fan has stopped turning; increase
fan speed to maximum and continue monitoring
Cooling Status Module Temp Shelf Manager Response
Nominal
specified by module
vendor
Continue monitoring module temperature
Upper Non-Critical Increase fan speed one step and continue monitoring
Upper Critical Increase fan speed to maximum and continue monitoring
Upper Non-Recoverable Increase fan speed to maximum, deactivate that module
and continue monitoring. This usually implies imminent
module damage if operation continues;