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Battery backup

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    Battery backup

    Anyone using a battery backup to keep their system running during a power failure? I'm looking for one to keep my router and one IP camera going for 3 - 4 hours if the power goes out. Any suggestions?

    A couple years ago, I purchased an APC Back-UPS750. It powers my iMac, a router, modem, 1 portable phone base station and 1 portable extension phone for about a day.

    Looking at the APC product line it appears the 750 has been phased out and the 850 has replaced it.
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      I'm using 2 APCs for my two desktops. I think my next UPS will be a CyberPower instead of APC. Both are good. My two will not last 3 to 4 hours.
      The test of success is not what you do when you are on top. Success is how high you bounce when you hit the bottom
      --General George Patton

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      ––Paul Nussbaum


        Originally posted by Yadier View Post
        Anyone using a battery backup to keep their system running during a power failure? I'm looking for one to keep my router and one IP camera going for 3 - 4 hours if the power goes out. Any suggestions?
        Our utilities are "below grade", so we tend not to suffer as many outages as other places I've lived. The outages that we do see tend to be momentary "light flickers" (I've noticed this happens, reliably, at 12:05AM every night -- maybe some sort of "switching transient"). It's questionable whether those momentary "winks" would crash a system -- but, I choose not to find out!

        I have UPSs on every machine/appliance, here (including the TV, of course -- what the heck am I going to do if the power DOES fail for an extended period of time? Ans: watch TV!).

        You need to estimate the amount of power (Watts) that you would like to keep "up". And, the length of time that you'd like to have those things available during an outage (you claim 3-4 hours). Don't forget to consider other uses that you might make of the UPS (recharging a powerchair? running a 13W CFL lightbulb in a light fixture?)

        For example, this computer (AIO), the 4 port router (no wireless) and the wireless link to my ISP are powered by an APC "SmartUPS 1000" (SMT1000). It happens to have a display that lets me examine its current operating conditions. It claims that it is currently supplying ~42W (~50VA -- more later) and, at that level, it should power the load for 2:39.

        OTOH, the table at suggests I should expect more than 3 hours! (Note that my computer probably represents a lot bigger load than your IP camera).

        UPSs are rated in VA (Volt-Amperes) instead of Watts. As a rough rule-of-thumb, the Watt rating of a UPS is about 70% of the VA rating. So, my 1000VA UPS is really only good for ~700W. This is only important if you are trying to push the limits of the UPS or have certain types of loads (motors are almost certain death for UPSs). If you know your load in VA, then think in terms of VA. If you know your load in Watts (like incandescent light bulbs), then think in Watts.

        Note that a UPS requires time to "recover" from powering the load -- cuz the batteries need to recharge! So, if you live somewhere that experiences repetitive outages (off for an hour, on for a few minutes, off for another hour, etc.) then you want to think in terms of the total time that you are without power as very little recovery will happen in any period when the power returns, momentarily.

        I think my UPS takes about 3 hours to recharge from "spent".

        A few other tidbits to consider:

        UPSs get warm -- when in standby but especially when actively backing up the load. Make sure you have a place that is well ventilated (they often have fans which come on when the UPS gets warm)

        Consider the number of "plugs" that you'll be wanting to plug into the UPS. Most have some number of "backed up" outlets and some number of "surge protected (BUT NOT BACKED UP)" outlets. You really don't want to have to add an extension cord just to get an extra outlet or two!

        UPSs like to make noise when they are backing up the load. This can be a life-saver -- or a real PITA! For example, that 12:05 glitch that I mentioned causes EVERY UPS in the house to snap on, momentarily. As a result, I have disabled the noise makers in all of them (some UPSs have a setting that lets you do this; others DO NOT!) Think about your smoke detector when it tries to alert you to the need for a new battery... not very appealing, eh?

        Most UPSs have some degree of smarts. This may be as simple as a (USB) cable that plugs into your computer (ideally, the computer that you are powering with the UPS as this allows the UPS to turn off the computer when it can no longer keep it powered up). Or, it may be a network connection that lets you "talk" to the UPS with a web browser -- from ANY computer on your network.

        Batteries go bad in UPSs. Sometimes pretty quickly (the cases tend to be poorly ventilated so the battery operates at a higher temperature -- which means shorter life. And, the UPS designers want to bring the battery back to "full capability" ASAP so they are very aggressive in their charging strategies (which can also shorten life).

        You will find small (~500VA) UPSs that have a single 12V battery; larger units that will have a pair of 12V batteries wired in series (24V); and other units that will place FOUR batteries in series (48V). As a result, you may find yourself buying one, two or four batteries at a time (I tend to favor the 12V 7.2AHr battery size at ~$25/each). Buying batteries from the UPS vendor will cost you considerably more than from third parties (I like buying from DigiKey -- but shipping can be costly).

        The most important tidbit is related to batteries: UPSs are frequently discarded simply because their batteries have died and the owner/user balked at the price that the UPS vendor wanted to charge for the replacement "battery PACK". So, its usually pretty easy to find someone who has discarded a UPS that can serve your needs.

        I have about a dozen of them, here. I doubt I've ever paid more than $5 for any of them (though often have to buy new batteries). I am continually upgrading them as I encounter newer/nicer units (e.g., my older UPSs didn't have these nice little displays so each time I find one with a display, I use it to replace an existing UPS (and pull the batteries from the existing UPS to avoid having to purchase new batteries for the "new" UPS).

        My old UPSs were: and similar. They have approximately the same performance as the SMT1000 but less glamorous displays, etc.


          One other item that can be important: some UPSs can only be turned on when power is available. Others can be turned on regardless of the availability of power (of course, if power is absent, then the batteries need to have a charge!)

          As I mentioned, I have lots of UPSs here. So, if power does fail for a prolonged period of time, I will run an extension cord down the hallway to a UPS that MAY NOT BE ON AT THE TIME. Then, plug in a table lamp to illuminate the room I'm in. As my UPSs can be powered on even in the absence of power, I can then power up the UPS and enjoy the light provided by that lamp. If the UPSs didn't have this capability, I would have to find a UPS that was already "on". But, if its on, then something else is probably sucking on its battery power, presently, so it may not be able to power the lamp for long!

          Note that CFL bulbs (and LED bulbs) draw much less power than their incandescent predecessors. So, I can run a 60 watt EQUIVALENT CFL bulb for 4 times longer than that 60W incandescent! (your neighbors will wonder why YOU have electricity -- cuz YOUR lights are on -- but they don't!


            Wow, so much information. Thanks everyone.