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SRT 8 or 10kVA reports Error P.11 or DC Bus Voltage Low or event codes 128/129

Issue: The UPS reports P.11 or DC Bus Voltage Low - event 128/129

Product Line: Smart-UPS SRT 8-10kVA Models

Resolution:
Clear the Alarm. Turn the output ON again. If the problem persists, Brain dead the UPS. If the alarm reoccurs, perform a UPS Firmware upgrade to the latest 04.7 revision that addressed these issues. For complete upgrade instructions please refer to FA164737.

Release Notes (UPS 04.7):
========================
1. Improved system performance of transitions between Online and Bypass operation modes.
2. Improved system behaviour for three phase input configurations to reduce transitions to battery under certain input feed conditions.
3. Improved system behaviour to eliminate false detection of DC bus under voltage alarm under certain conditions.
4. Improved system handling for certain AC input conditions during system start-up.