nStor NexStor 4700F Series, User Manual

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Chapter 1 - Getting Started
Cooling Fan Module
9
If a power supply reaches 85°C (185°F), it will shut down.
Normally, the fan speed is controlled automatically. It will maintain fan speed RPM
at the minimum RPM required to maintain effective cooling. Should a condition
occur that requires a greater volume of air, the fan RPM will increase up to the
maximum to maintain cooling temperatures. The ability to maintain low RPMs
allows the system to operate in a noise sensitive environment.
A manual override of the fan speed control is available for special circumstance
environments. Referring to the illustration on the preceding page, two jumpers are
provided on the fan module printed circuit board to override the software control
of the fan speeds. This hardware setting routes full power voltage to the fans for
maximum operational speed, which is greater than the maximum speed set by the
automatic software control. This configuration is normally used when fan speed
noises are not an issue, and the ambient operating temperature is at or above 30°C
(86°F), thus ensuring that maximum available cooling is being provided.
The jumpers JP1 and JP2 by default are offset, which enables the automatic fan
speed control. The jumper JP1 controls Fan 0 and JP2 controls Fan 1. Placing the
jumper on both pins for each jumper will override the automatic setting and
configure the fans to maximum power.
4700F.book Page 9 Wednesday, April 6, 2005 11:05 AM