A UPS will have a load. It's got to keep the battery healthy.
They are intended to keep a more vital system up. Generally a NAS is the backup target. And you'd keep the computer is it the target for on the UPS. Maybe the NAS too.
You can probably get away with a desktop UPS. But the power draw is always going to be a factor. The NAS is designed to stay on all the time. So is low power draw.
A UPS will have a load. It's got to keep the battery healthy.
They are intended to keep a more vital system up. Generally a NAS is the backup target. And you'd keep the computer is it the target for on the UPS. Maybe the NAS too.
You can probably get away with a desktop UPS. But the power draw is always going to be a factor. The NAS is designed to stay on all the time. So is low power draw.