Fault
CyberPower UPS
Severity: CriticalWhat Does This Error Mean?
A Fault indicator on a CyberPower UPS means the unit has detected an internal hardware problem it cannot self-correct. The UPS will shut off output to protect connected equipment. Try cycling power (disconnect from wall, wait 30 seconds, reconnect). If the fault persists, the UPS likely needs repair or replacement.
Affected Models
- CyberPower CP series
- CyberPower BR series (online models)
- CyberPower OL series (online double-conversion)
- CyberPower EC series
Common Causes
- Internal inverter or charger circuit failure
- Overheating due to blocked ventilation or very high ambient temperature
- Input mains voltage severely out of range (very high or very low)
- Short circuit on the output caused by a faulty connected device
- Firmware corruption after a power disturbance during a firmware update
How to Fix It
-
Disconnect all devices from the UPS output. Disconnect the UPS from the wall socket. Wait 30 seconds, then reconnect to mains power with nothing connected.
A short circuit on the output caused by a faulty connected device can trigger a fault that clears once the load is removed. If the fault clears, reconnect devices one at a time to find the faulty one.
-
Ensure the UPS ventilation slots are clear. Move the UPS away from walls and other equipment to allow airflow. Let it cool for 15 minutes in a well-ventilated area.
CyberPower UPS units have cooling vents on the sides and back — these must not be blocked. Overheating is a common cause of fault shutdowns in warm environments or tight cabinets.
-
If the fault indicator reappears after power cycling, the UPS has an internal hardware fault and should not be relied upon. Contact CyberPower support for warranty service or replacement.
CyberPower offers a Connected Equipment Guarantee — if equipment is damaged due to a UPS fault, they may cover the loss. Document the fault and contact support with the model number and purchase date.
Frequently Asked Questions
Is it safe to continue using a CyberPower UPS showing a fault indicator?
No — a UPS with a persistent fault indicator is in an unknown state and cannot be trusted to protect connected equipment. Switch to an alternative power source and stop using the UPS until the fault is resolved.