What is the primary function of a Standby UPS in normal mode?

The primary function of a Standby UPS (Uninterruptible Power Supply) in normal mode is to act as a filter for utility power. In this mode, the UPS allows incoming utility power to pass through while monitoring the power supply for any irregularities, such as voltage fluctuations or outages.

When the utility power is stable and within acceptable parameters, the UPS does not provide power from its internal battery; instead, it allows the connected devices to draw power directly from the wall outlet. This operation effectively filters and conditions the utility power, protecting connected equipment from subtle fluctuations or spikes that can cause damage or malfunction.

While other options mention continuous power supply, energy storage, and DC to AC conversion, those functions primarily occur under different circumstances. For instance, the UPS switches to its battery mode during a power outage to supply continuous power to connected devices, but this is not its primary function in normal mode. The energy storage aspect refers to the UPS's capability to sustain power during outages but is not related to normal operation. Lastly, the conversion of DC to AC happens when the UPS is supplying power from its internal battery during an outage, not in normal mode when it’s filtering utility power.