Thermal Monitoring And Control - Lenovo Storage D1212 Hardware Installation And Maintenance Manual

Table 20. Alarm Conditions (continued)
Status
Over-temperature alarm
Under-temperature alarm
2
I C bus failure
Ops panel communication error (I
RAID error
ESM fault
ESM removed
Drive power control fault
Drive power control fault
Insufficient power available
For details on how to remove and replace a module see Chapter 6 "Module Removal and Replacement" on
page 75.

Thermal Monitoring and Control

The enclosure system uses extensive thermal monitoring and takes a number of actions to ensure that
component temperatures are kept low and also to minimize acoustic noise. Air flow is from the front to the
rear of the enclosure.
Symptom
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
condition.
2
C)
Cause
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: This threshold changes
according to the number of drives
and power supplies fitted.
Severity
Fault – critical
Fault – critical
Fault – loss of redundancy
Fault – critical
Fault – critical
Fault – critical
Warning
Warning – no loss of drive power
Fault – critical: loss of drive power
Warning
Action
1. 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.
2. Check for restrictions due to dust buildup.
Clean as appropriate.
3. Check for excessive recirculation 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.
5. Reduce the ambient temperature.
.
Chapter 5 Troubleshooting and Problem Solving
65