Why Is There No Power Output from the UPS?
First, the most common scenario: the **mains power** is cut off, and the UPS battery is also depleted. When the mains power is interrupted, the device is powered by the UPS battery. If you experience a prolonged power outage, the battery will be completely drained, and the UPS will automatically shut down to protect the battery—this is why there is naturally no power output. You can check the remaining battery capacity on the display panel of the Shanshuo UPS; if the battery shows it is nearly dead, this situation will occur. After the mains power is restored, the UPS usually needs to charge for several hours to resume normal operation.
The UPS may also enter an **overload or short-circuit protection state**. If the total power of the connected devices exceeds the rated output power of the UPS, or if a short circuit occurs, the UPS will activate self-protection and automatically cut off the power output.
Another core cause is **battery aging or failure**. Most UPS systems use rechargeable batteries (typically sealed lead-acid batteries), which have a lifespan of approximately 2–3 years. As usage time increases, the battery will gradually lose its ability to store sufficient power. Even if the mains power is normal, an aging battery will cause the UPS to fail its self-test, preventing it from starting. We recommend using a **lithium-battery UPS**: lithium batteries have a lifespan of up to 5–8 years, eliminating the need for frequent battery replacements. The lithium-battery UPS uses lithium iron phosphate batteries with a high safety factor, so there is no need to worry about battery safety issues.
In addition, **faults with the UPS itself cannot be ruled out**. Examples include damage to internal components such as the inverter or control circuit.