Uninterupted power (battery backup)

[Dr Joe]

A deep cycle battery can safely be discharged to low levels several (hundred) times.

You can find one at any automotive store. That is a good idea to use a few deep cycles wired in parallel and use the UPS as a switching device.

Hooking them in parallel can have problems...if internal resistance of the batteries are different the lowest one will drain the others and you won't get your full run time. If you went with multiple batteries there is a switch used for boating (mainly) to select each battery (and an auto-select for charging)

 

[Dr Joe]

Can you tell me more about the UPS with a deep cycle battery, how and where would I acquire this? What the hail is a deep cycle battery? My dilema is my power company is shutting down our neighborhoods power for 5 hours for maintenance purposes.....

Finding a used UPS ? Try some computer repair shops (I used to have several dozen in my shop warehouse). See if there is an online group in your area called 'freecycle' it's people with stuff to 'give' away.

Google about deep cycle batteries. They're used with trolling motors for fishing, electric carts and electric wheel chairs to name a few things.

To use one with a UPS, the battery must be FULLY charged. If you feel uncomfortable doing any of this find someone who is qualified. Some UPS's can hold a charge of either AC or DC for a period of time. Open up the UPS and find the internal lead acid battery. Mark the wires from the battery positive and negitive, then disconnect the wires from the battery and properly discard the old battery. Lengthen the wires with a heavy gauge wire from the UPS so they can comfortably reach the new deep cycle battery, use marine battery connectors, they have screw-on terminals (get a case for the battery). Insulate all new connections with heat shrink tubing and good electrical tape. With the new battery FULLY charged, hook the wires from the UPS to the proper terminals on the new battery. The reason I state FULLY charged is that the UPS will not charge the battery if it is very low, it will blow a fuse or burn up the charge circuit. It will 'maintain' a charge on the new battery tho. Once done close everything up, making sure no wires are pinched at or in the UPS.
Plug in the UPS to grid power and turn on, if everything was done right there will be NO smoke and if it has a power on indicator it will be on. Add up all the power requirements of your equipment (in watts) and plug in an equivalent lamp (100-150 watt light bulb etc.)
lamp should lite normally (DO NOT go over the UPS's recommended rating). Now unplug the UPS and it should transfer over to the battery without even a flicker (depending on the UPS). If that went well, turn off the UPS and plug it back in. Now make note of the time and unplug the UPS and time how long lamp remains lit. When UPS battery gets low most have an alarm to warn you of it. If you test it to its fullest extent remember that you will have to disconnect the battery and recharge it fully with a suitable charger BEFORE plugging the UPS back in.

Well don't think I missed much, if it works great.. yor welcome. If it goes up in flames take pictures and remember...IT'S NOT MY FAULT !

If you do this be sure and keep us posted and good luck.

 

[rallysman]

Hooking them in parallel can have problems...if internal resistance of the batteries are different the lowest one will drain the others and you won't get your full run time. If you went with multiple batteries there is a switch used for boating (mainly) to select each battery (and an auto-select for charging)

I forgot about the batteries possibly "fighting" each other, I'm glad you pointed that out

I'm used to charging them while they are in use so I didnt think about that, but you're right!