Problem:
When the UPS is running at a high load a power block and temperature beyond the specification can be declared inoperable due to a "Power block inverter heatsink temperature out of tolerance" (power block high-temperature event).
Environment:
Startup phase, FSR testing UPS with load, HVAC design and implementation, Break Fix, Temperature alarms activated in the UPS or UPS room. Normal operating status with loads

Possible Cause:
The following causes power block high-temperature alarms:

1. If the dust filter is accumulated with dust, fresh air cannot flow inside the power block.
2. A faulty or reversed fan.
3. The inverter is shut down by a thermostat on the heat sink if the temperature rises above 55°C, which is the maximum.
4. If the UPS exhaust sections are restricted and turbulent airflow.

Solution:

1. Check the ambient temperature in the UPS room (Air-cooling should be within 35°C)
2. Check the dust filter condition. If the dust filter is accumulated with dust, clean the dust filter which will result in fresh air flow inside the power block.
3. Verify all fans in the power blocks function correctly.

Caution: If the ambient temperature in the UPS room cross over 40℃, then the UPS load will shift to bypass operation.
Note: If the above conditions meet, an FSR visit is required to check UPS parameters and event logs. Please contact Schneider Electric.

Released for: Schneider Electric India