Thermal Monitoring And Control; Thermal Alarm - IBM Small J10 Series Manual

Thermal monitoring and control

The small disk enclosure system uses extensive thermal monitoring, and takes a number of actions to
ensure component temperatures are kept low, and also to minimize acoustic noise. Air flow is from the
front to the rear of the enclosure.
Table 15. Thermal monitoring and control
Symptom
If the ambient air is below 25 °C
and the fans are observed to
increase in speed then some
restrictionon airflow may be
causing additional internal
temperature rise.
Note: This is not a fault
condition.

Thermal alarm

Table 16. Thermal alarm
Symptom
1. Ops panel modulefault LED is
amber.
2. Fan fail LED is lit on one or
more PCMs.
30 IBM Cloud Object Storage System: IBM Small J10 Disk Enclosure Manual
Cause
Thefirst 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: This threshold changes
according to the number of drives
and power supplies fitted.
Cause
Internal temperature exceedsa
pre-set threshold.
Action
1. Check the installation for any
airflow restrictions at either
the front or rear of the
enclosure. A minimum gap of
25mm at the front and 50mm
at the rear is recommended.
2. Check for restrictions due to
dust build-up. Clean as
appropriate.
3. Checkf or excessive re-
circulation of heated air from
rear to the front. Use of the
enclosure in a fully enclosed
rack is not recommended.
4. Check that all blank modules
are in place and secure.
5. Reduce the ambient
temperature.
Action
1. Check that the local ambient
environment temperature is
below the specification.
2. Check the installation for any
airflow restrictions at either
the front or rear of the
enclosure. A minimum gap of
25mm at the front and 50mm
at the rear is recommended.
3. Check for restrictions due to
dust build-up. Clean as
appropriate.
4. 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.
5. If possible shutdown the
enclosure and investigate the
problem before continuing.