Harmonic MediaGrid - Thermal Alarm

Chapter 9 Troubleshooting
© 2017 Harmonic Inc. All rights reserved. 293 Harmonic MediaGrid Release 4.1
Troubleshooting the ContentStore 5840
Thermal Alarm
Symptom Cause Action
If the ambient air is below
25 ° C
and the fans are
observed to increase in
speed then some restriction
on airflow may be causing
additional internal
temperature rise.
Note:
This is not a fault
condit
ion.
The first stage in the thermal
control
process is for the fans
to automatically increase in
speed when a thermal
threshold is reached. This may
be caused by higher ambient
temperatures in the local
environment and may be
perfectly normal.
Note: T
his threshold changes
accor
ding to the number of
drives and power supplies
fitted.
 Check the installation for any airflow
restrictions at either the front or rear of
the enclosure. A minimum gap of 25
mm at the front and 50 mm at the rear
is recommended.
 Check for restrictions due to dust
buildup. Clean as appropriate.
 Check for excessive re-circulation of
heated air from rear to the front. Use
of the enclosure in a fully enclosed
rack is not recommended.
 Check that all blank modules are in
place. Reduce the ambient
temperature.
Symptom Cause Action
 Operator’s panel module
fault LED is amber.
 Fan fail LED is lit on one
or more cooling modules.
The internal temperature has
excee
d
ed a pre-set
threshold.
 Check that the local ambient
environment temperature is below the
specification (see Temperature and
Humidity).
 Check the installation for any airflow
restrictions at either the front or rear of
the enclosure. A minimum gap of 25
mm at the front and 50 mm at the rear
is recommended.
 Check for restrictions due to dust
buildup. Clean as appropriate.
 Check for excessive re-circulation of
heated air from rear to the front. Use
of the enclosure in a fully enclosed
rack is not recommended.
 If possible shutdown the enclosure
and investigate the problem before
continuing.