Which UPS for 4x BTX 12-75LS

[ad3m]

Hello,

I have four of BTX 12-75LS batteries and i want to use them for an ups. now i want to ask which ups can support these batteries? like for charging and supply the devies for like max 300w.

 

here you can find the battery:

https://www.vkibt.hu/uploads/vkibt-1494511132_1.pdf

 

maybe an apc usv?

[Constantin]

Those batteries are huge!!!!!

75Hv.....LOL

One of those is for a car.....

There is no way you will find a UPS to match them in.

Except if you build it yourself.

 

 

 

 

 

 

[Constantin]

Can someone with knowledge check if this is clean?

3 hours ago, ad3m said:

https://www.vkibt.hu/uploads/vkibt-1494511132_1.pdf

 

[ad3m]

these batteries are used for an ups. they changed in a backbone like 50 of them and i could take 4 four of them. i want to use the full power of the battery. i just need max 300w.

[mariushm]

You could buy a 48v pure sine wave inverter, for example this Victron that can do 375w (700w peak) : https://amzn.to/2EVkyFn

 

It can take up to 62v and produces 120v DC  (you're linking to a Hungarian website, if you're in Hungary then you'll want a 230v pure sine wave inverter but a 120v one would work with computers or other things that have switching power supplies)

 

You could wire those 4 batteries in series and then you just need to source a power supply that can pump around 13.5v x 4 = 54v into the batteries.  Datasheet says 2.29v per cell - 3mV per degree C above 25c, so 2.29v x 6 = 13.74v per cell, but you can just be conservative and go with 13.5v

A lot of industrial 48v power supplies will have potentiometers that would allow you to adjust output and give 50v+

For example this 500w meanwell psu can do up to 56v : https://www.digikey.com/product-detail/en/mean-well-usa-inc/RSP-500-48/1866-4279-ND/7706343

 

so psu  AC -> 48v..54v DC -> battery -> inverter -> 110v/230v

 

But the batteries will be a bitch to charge due to their super low internal resistance... they're also huge at nearly 80A each,,, with just a 500w power supply it would take probably 2-3 days to have them topped up .. I'm too lazy to do the math.