How long do those backup batteries last?
- Thread starter rykwong
- Start date
You gotta do a little math:
Volts * Amps = VA
To get runtime on a UPS use the following calculation (taken from http://www.mhpower.com.au/nikobe/html/sizingguide.html)
"Divide the rating in VA of the UPS by the rating in VA of the load. If the result is less than 1.3 these calculations cannot be used. Where the result of the above division is greater than 1.3 but less than 3, multiply this result by 1.3 x the full load backup time of the UPS to obtain the backup time at the lower load. Where the result is greater than 3 user a 1.5 multiplier.
Examples:
600VA UPS with full load backup time of 10 minutes.
Load of 250 VA. 600/250 = 2.4. So multiplier is 1.3.
Therefore, backup time for 250 VA load on 600VA UPS = 2.4 x 1.3 x 10 = 31.2 minutes approximately.
Load 120 VA. 600/120 = 5. So multiplier is 1.5
Therefore backup time for 120 VA load on 600VA UPS = 5 x 1.5 x 10 = 75 minutes approximately."
Factors throwing these results off would be overhead, startup load, differences between inductive loads -vs- electronic loads etc, but this will give you a general idea. The best way to tell is to do a dry (or wet in our case) run with your UPS and load.
Volts * Amps = VA
To get runtime on a UPS use the following calculation (taken from http://www.mhpower.com.au/nikobe/html/sizingguide.html)
"Divide the rating in VA of the UPS by the rating in VA of the load. If the result is less than 1.3 these calculations cannot be used. Where the result of the above division is greater than 1.3 but less than 3, multiply this result by 1.3 x the full load backup time of the UPS to obtain the backup time at the lower load. Where the result is greater than 3 user a 1.5 multiplier.
Examples:
600VA UPS with full load backup time of 10 minutes.
Load of 250 VA. 600/250 = 2.4. So multiplier is 1.3.
Therefore, backup time for 250 VA load on 600VA UPS = 2.4 x 1.3 x 10 = 31.2 minutes approximately.
Load 120 VA. 600/120 = 5. So multiplier is 1.5
Therefore backup time for 120 VA load on 600VA UPS = 5 x 1.5 x 10 = 75 minutes approximately."
Factors throwing these results off would be overhead, startup load, differences between inductive loads -vs- electronic loads etc, but this will give you a general idea. The best way to tell is to do a dry (or wet in our case) run with your UPS and load.
You're welcome.
For the impending outtage on Friday in my neighborhood, I plan on having around 200W load on a 2200VA UPS.
To get amps, using ohms law:
Amps = Watts ÷ Volts (I=P÷ E)
I=200 ÷ 120 = 1.6A
VA = 120 * 1.6 = 192VA for my load
2200 / 192 (Rating of UPS / My VA load) = 11.46
We will use a 3 multiplier (see above).
Full load runtime of this UPS is 5.2 minutes (at 1980 watts)
11.46 * 3 * 5.2 = 179 minutes. Im in trouble!
I need 8 hours. SO I probably wont run heaters, and I need some battery operated air pumps.
For the impending outtage on Friday in my neighborhood, I plan on having around 200W load on a 2200VA UPS.
To get amps, using ohms law:
Amps = Watts ÷ Volts (I=P÷ E)
I=200 ÷ 120 = 1.6A
VA = 120 * 1.6 = 192VA for my load
2200 / 192 (Rating of UPS / My VA load) = 11.46
We will use a 3 multiplier (see above).
Full load runtime of this UPS is 5.2 minutes (at 1980 watts)
11.46 * 3 * 5.2 = 179 minutes. Im in trouble!
I need 8 hours. SO I probably wont run heaters, and I need some battery operated air pumps.
raskal311
New member
All that is great to have on hand in case of an emergency but why not just rent a generator since you already know that the power will be out. You never know about the electric company they say 8 but it could as well be 4….12…24…48+ hours for all you know. Remember hugo? they said a x hours but it turned out to be days..
Raskal is probably right but in case you still want to get a UPS...
http://store.pagecomputers.com/catalog/Power_Equipment/UPS_Systems/Standby/760493.html#tab_overview
I just happen to run across this. I don't own one so I have no idea if it is any good. Just passing info along...
Kelly
http://store.pagecomputers.com/catalog/Power_Equipment/UPS_Systems/Standby/760493.html#tab_overview
I just happen to run across this. I don't own one so I have no idea if it is any good. Just passing info along...
Kelly
laverda
Well-known member
KWoo008; Thats a real good price for 1000VA.
rykwong and any one else considering using a battery backUP. Not all pumps will run on battery backups. They also tend to run hotter. Also the larger 800+ ones usually have betterwave form for running pumps. You best bet is to get on and run you pump and see what happens. Inother words try it out before you need it. I have a 1000VA one with additional batttery pack(tripples my VA) for my main 15th HP pump and it works well. The pump is a little noisy and runs hotter, but it will run fo over an hour on the bac`k up. A tunze nano stream at only 7 Watts would be ideal for this application, if they will run on the BackUPS. http://www.marinedepot.com/md_viewItem.asp?idproduct=TZ1211
The cheap battery air pumps last a long tim and work well. http://www.marinedepot.com/md_searc...ext=Aeration&step=1&itemsonpage=15&Clearance=
rykwong and any one else considering using a battery backUP. Not all pumps will run on battery backups. They also tend to run hotter. Also the larger 800+ ones usually have betterwave form for running pumps. You best bet is to get on and run you pump and see what happens. Inother words try it out before you need it. I have a 1000VA one with additional batttery pack(tripples my VA) for my main 15th HP pump and it works well. The pump is a little noisy and runs hotter, but it will run fo over an hour on the bac`k up. A tunze nano stream at only 7 Watts would be ideal for this application, if they will run on the BackUPS. http://www.marinedepot.com/md_viewItem.asp?idproduct=TZ1211
The cheap battery air pumps last a long tim and work well. http://www.marinedepot.com/md_searc...ext=Aeration&step=1&itemsonpage=15&Clearance=
