UPS and backup battery

I appreciate all the great info as well. Didn’t mean to hijack your thread Kojack :wink: as I’m looking for a similar solution to power outages. I want a UPS to maintain power for a brief period but if necessary initiate a graceful shutdown and if power is restored, bring my PC and (WD!)back to life. :slight_smile: --Bill

I hope Belkin changed the firmware since they made mine (2-3 years now), one of its dumb tricks is that if you set it to shut down "x" minutes after line power fail, it will do exactly that, go ahead and kill power to your PC even if the failure was short and line power has come back on the meantime

The solution to that is to set the Bulldog software to shutdown the OS when what it determines is “battery low”, which from my test was at about 20% battery remaining. That way if power restored before low battery is reached, the battery will begin to recharge and low battery will never be reached.

That’s what I do (actually @ 60%), but my point was that to design the timed shut down so that it doesn’t abort if the power is restored makes no sense.

Does yours have the restart option?

Yes I agree, that makes no sense at all if power is restored!

But you have me a bit baffled, why would you shutdown at 60% with all that battery remaining?

And no I don’t believe I have the restart option, my question here is why wouldn’t it simply start back up if power restored if I did not check the box to power it off.

You know, I had a very good and logical reason at the time, but it escapes me now #-o

my question here is why wouldn't it simply start back up if power restored if I did not check the box to power it off.

If the batteries do not reach the shutdown point, then there you are right, there’s no issue, but if the batteries reach that point and it shuts down, then it’s not going to start up again and the PC won’t see power again until someone pushes the button on the UPS. That’s fine if it’s under your desk, but one of mine is 250 miles away.

Here is one more you may want to consider. Doesn’t have all the fancy stuff but looks to have a long life. Of course they all lie and I haven’t lost power for more than a few seconds so can’t speak for the battery life.

It’s an XPower PowerSource 400 from Red Orbit. $130 and about $25 shipping.

I’ve got desktop, monitor, and satellite modem connected. May do a test tomorrow and see how long it will last. One thing I do like is the size. Nice and narrow, not bulky at all and doesn’t seem to put off much heat.


If you read the spec that’s a very interesting unit, it has a 40 aH battery, but the whole thing only weighs 32 lbs.

[quote author=nikoshepherd

But what about the transformer and electronics? All the ones I have include a big, heavy, transformer too. Now this is only a 400 va unit so it won’t be a HUGE transformer but it’s hard to imagine that the transformer and the other stuff is less than 3lbs :?

It’s quite common to do this. I think the discussion here is about trying to keep systems running right through an extended power outage. Many UPSs are configured just to give the attached systems a soft bounce if the power does go off. For example, at work we have many of our UPS connected servers set to shut down after 5 minutes without power (and of course the shutdown needs some time to complete which on servers can be much longer than a home PC). Maybe this is a more common way of working in the UK where we get very few outages (I can’t remember the last time I lost power at home).

A significant issue for UPS owners is what does 60% battery capacity remaining actually mean and how long will that really last with your own set of equipment connected to it? Battery capacity degrades over it’s lifetime and measuring remaining battery life is difficult. The only effective way to do it is to run a simulated power outage on the UPS to see how long it lasts before it gives up! Given the uncertainty of how much capacity the UPS really has, carrying out a shutdown at 60% (or even higher) is a safe bet.

There’s also an issue if you run a UPS down to empty. Some UPSs won’t re-start until they have a minimum amount of charge in them. So you might find that once the power returns you still can’t get your PC up and running. Also if you run the UPS until it’s empty, if the power comes back on for a few minutes, i.e. long enough to get the PC back up and running, but not long enough to charge the UPS battery, your PC will come crashing down if the power goes off again shortly afterwards because there won’t be enough charge left in the UPS to give it time to shut down gracefully.

I don’t know what other people’s power outages are like, but I know I’ve seen them in the past where the power goes off, comes on, goes off again, comes on again, etc…as they try fixing the problem.

So 60% is a reasonable capacity to use for a shutdown, although I’m not sure what happens if you get to 60% and then the power comes back on to get you to 61% and then goes off again!

I don’t know if anyone is mention it, but there are two kinds of UPS, the stand by one and the on-line one. The on-line one uses the batteries (charge and supply at the same time) to supply power all the time so if the batteries are down no output will present till they charge, these units supply a clean mains power with no voltage variations, the stand by one will switch to batteries when mains is down and will be back on again when mains is present with no need for the batteries to be charged at any level, some of them have a delay for switching back on for safety reasons. I haven’t seen one yet that needs to be switched on manually after a power failure (unless is an on-line one, but will come on by it’s self once the batteries charge). So a home UPS is only good for very short power failures and for shutting down the PC if it happens unless you run a genaretor (then you can still be with out power if the genaretor battery goes down :lol:). The shut down at 60% battery I think applies to on-line UPS so you get a restart at mains restore but if you need a 1/2 an hour of back up, a shut down at 60% and start at restore you are looking at a 2,5 kVA plus UPS just to run a PC, or a 1,2 kVA for a stand by one and of course as time goes by the capacity of the batteries reduces and the back up time gets shorter and shorter.

Here’s one, and it’s not an online type either :wink:


Now I’ve seen it all, but I can’t see a reason why not to switch on after power restore?

I just bought a new (refurbished) one for my computer rack. Very reasonable pricing.

It will be around 1/4 load when everything is in it so uptime should be closer to 35-40 mins or there abouts.

We mainly have short power outages here with line spikes. Anything of long duration (more than an hour) will need a generator which I just can’t justify right now, only has happened 3 times in 12 years here. We don’t have hurricanes here so there is little point it continued broadcast during an outage unless a volcano blows in California or something :blob6:

Power Ratings: 950 W / 1400 VA

*Est. Runtime (Half Load): 23.5 minutes

*Est. Runtime (Full Load): 6.6 minutes

Rackmount Height: 3U

Input Voltage: 120 V

Input Plug Type: 5-15P

Input Plug Length: 6 ft

Output Voltage: 120 V

Output Types: (6) 5-15R

Interface Port:Serial (DB-9 RS-232)

Dimensions (in inches): 5.2 in (H) x 17 in (W) x 15.5 in (L)

For a home PC, probably little reason. For bigger server based architectures you may want to bring the servers back up under human control to make sure what state they were in when shut down. You may also want to ensure that certain servers re-start before other servers.

Talk about beating a dead horse :slight_smile:

Ok I just ran a test on my Belkin 1100VA

Pulled the plug, let it run it’s course and powerdown PC at low battery this time (~ 30%). All sources on the UPS were shutoff including the cable/modem, no power was being drained from the UPS, then it shut itself off. I let things sit about 5 minutes, plugged AC back in, the UPS came back on (Green light indicator) without any intervention, cable/modem came back on, but the PC had to be manually powered up, I assume having to do with the Bios discussion going on in this tread.

As pinkpanther mentioned, there is more than one benifit from having a UPS
From Belkin Site:

Ok so I agree with the above but when your server goes down due to power, don’t have them power up again when power restores, your UPS can come back on do it’s job to charge the batteries and you can start the machine when and how you want to start it. Besides that, big systems like you say always have genaretors for running, it only takes us 8 sec. to have full power again from a genaretor (140kVA) so our systems never shut down, only for maintenance or upgrades we shut down.

I have a APC 1500 VA smart ups and I am very happy with it. I cycle the battery about every 60 day, unplug power and let computer run battery down to about 30%. I know my computer and monitor, router, modem will run that long. We have a lot of power bumps and high voltage. I think the UPS is better than a battery backup unit. The ups filters the power for any problems, it trims high voltage or boosts up low voltage, and filters out spikes. Some backup units do not have sine wave power but have square wave output which effect some computer clocks. Some model of APC UPS you can plug in additional battery for longer run times (daisy chain). Joe

Good, they got smarter :smiley: Can you post the exact model number?

I think there might be some confusion here! I was talking about re-starting servers manually, not the UPSs themselves. I’d agree that when the power returns a UPS should re-start itself and start to recharge it’s batteries.

Not all big systems run on generator UPS systems. We don’t have any generator based supplies for our systems. One of our computer suites does have a battery based UPS that can supply the entire room (and a lot of the rest of the building) with power for up to 24 hours if required. There are some BIG banks of batteries! In other cases we have smaller battery based UPSs and also down to individual rack UPSs in other cases. We work on the assumption that if we’ve lost power to the computer suites, then we’ve lost power to to the rest of the site and that means that virtually all of the PCs and other powered devices on site will be off. There’s not much point running servers if no-one can make use of them!