generators, clean power, "true" U.P.S. vs "Back-UPS"

[Anonymous user]

We've been on generator power for a couple days (NJ, Isaias).  All the electronics were initially unplugged because early on the power cycled a few times.  I have used a gaming computer and charged a laptop a few times.

Anyway, today I wanted to get something off a home NAS protected by a BR1000G ("Pro 1000"), so I turned them on.  The NAS shut down after a bit.  The "UPS" sees 115v but isn't charging the battery and the battery ran out. According to the troubleshooting chart for the "UPS"...

The AC input voltage is out of range, the frequency is out of range, or the waveform is distorted

That sounds right.  Generators are known to have dirty power and it's a cheap generator.  On one hand I think "nice, it's protecting my NAS from dirty power."  On the other hand

1. It can't even charge its own battery with dirty power?
2. Isn't it supposed to clean the power?

I unplugged all loads and adjusted the sensitivity and it still wont charge.  Then I do some searching and find an article describing the difference between "true" "Uninterruptible power supplies" and "battery backups".

According to the article, only the former provide clean power when the input power is on and some battery backup products are labeled "UPS" by some manufacturers even though they're not true UPSs.  Sure enough, checking the manual for my "Back-UPS" product, I don't see "uninterruptible" used anywhere.

Is this correct?  I have a "battery backup" product that is not a true UPS despite having "UPS" written all over it?

[BillP]

Hi Troy,

I'll give you a short answer that's close enough and a really long answer, there is more than two types of UPS but we'll focus on three:

Standby - Battery kicks in when power is off or unacceptable, output inventor is off 

Line interactive - Battery kicks in when power is off or unacceptable but also does a higher level of cleaning, (particularly around voltage not really around the wave) and is faster to react, the output inventor is always on.

Double conversion or "Online" - All power is cleaned and outputted as a sin wave approximation, "dirty" power comes in, it's converted to DC which with the battery powers the output inverter which converts it back to AC, this is what we recommend for generators but it is almost our most expensive. (There is also delta wave conversion but I'm not an electrical engineer so we'll leave that alone)

The long answer is to have a look at this white-paper, like I said I'm not an electrical engineer but I understood most of it so you might be okay, Obvious I work with a lot of UPSs so that probably helped me understand.

  https://download.schneider-electric.com/files?p_Doc_Ref=SPD_SADE-5TNM3Y_EN

[chefash_apc · Accepted solution]

The terms UPS and Battery backup arent really set in stone.  They dont have any clear definitions.   

APC used to distinguish between their Backups v. Smartups lines to imply the type of power conditioning/protection that they offer.   But even that has merged because AVR technology is so cheap.

So now all APC units are power protection devices... protect against bad power and no power.

The cheapest way to protect power now is to use the batteries to condition the power and replace the power during an outage.   This means the batteries become depleted if it has to do this power conditioning continuously.

The other UPS alluded to by the other response was an Online UPS.   This type of UPS will say "Online".. like Smart Online in the name.  In these units, the UPS takes any sort of trashy power, converts it to DC, the rebuilds it to AC.  This Double conversion works great for generators as it does not care what power or frequency you give it, it will still keep the batts charged and create perfect power out.  APC models starting with SURT and SRT are your online units.  Liebert's line uses GXT to signal online.   Tripplite... SU

BTW - check you generator's frequency.  Often its the frequency that is off, more so than the AC voltage.