Cheap, low-power UPS

[Anonymous user]

I am in the market for a new UPS for a low-power system (~120W). Price is a crucial factor, so I'm thinking of a budget product, specifically a Back-UPS or a Smart-UPS SC. Any reason why I should choose the latter over the former? Admittedly, the SU-SC looks more reliable, though it's been called on this forum a Back-UPS on steroids. Is it just the metal case, though, or has some of the SU ruggedness also rubbed off the little brother?

[Anonymous user]

I am in the market for a new UPS for a low-power system (~120W). Price is a crucial factor, so I'm thinking of a budget product, specifically a Back-UPS or a Smart-UPS SC. Any reason why I should choose the latter over the former? Admittedly, the SU-SC looks more reliable, though it's been called on this forum a Back-UPS on steroids. Is it just the metal case, though, or has some of the SU ruggedness also rubbed off the little brother?

[BillP]

If your looking at price, the obvious choice is the Back Ups line. There is virtually no difference between the Back Ups and Smart Ups SC lines (BR and SC). Just look at the tech specs for your self.

When protecting your equipment you shouldn't ask "what's the cheapest"? You should ask "Whats the best?". That way your equipment is protected (Just like your personal life 😉 )

[BillP]

They both have the same sensitivity settings, though on that note, all of the SC models have at least boost and the BR500 is the one BR model that doesn't have boost or trim. So the extra weight in the 420 is for the transformer, which can adjust the incoming voltage in certain scenarios rather than switch to battery. So the SC models also have transfer points for the automatic voltage regulation (AVR) which this particular BR model does not.

[BillP]

Less technical answer:

The SC models are basically like a Back-UPS RS (prefix BR) on steroids. Both of these models are better than the entry level Back-UPS ES family (prefix BE). The SC models are pretty rugged, though they aren't too different from the BRs.

More technical answer:

The Smart-UPS SC is a lot like the Back-UPS RS models, which is a step above the Back-UPS ES. The SC has smart signaling so you can get some more info in terms of input/output voltages, battery capacity, runtime, etc via software.

The Back-UPS ES models have the longest transfer time (8-10ms) whereas the SC and BR models are shorter (4-5ms), depending on sensitivity settings. That may or may not make a difference for your config.

The [SC420|http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=SC420] can handle 260w, the [BR500|http://www.apc.com/resource/include/techspec_index.cfm?base_sku=BR500] can do 500w, and the [BE450G|http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=BE450G] can do 257w. Pretty decent price difference but whether or not you want to pay for the few extra features is up to you.

[Anonymous user · Accepted solution]

thanks, i've already shortlisted the SU-SC and the BU-BR. do they offer the same amount of control over the unit's parameters (sensitivity, etc.)?

i mean, i assume there is a good reason why a SC420VA is 9kg in weight, while the BR500VA is 6.5kg, with the same battery inside. i know they both produce a stepped approximation rather than a sine, but i imagine there could be better technology inside to account for the additional kilo or so (discounting the metal casing)