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Size of UPS

A rough estimate for Kva seen in an article

eg. You have a 4U high switch with a 350W (real power load), to get the apparent power load (kVA, the UPS unit), take 350W/0.8 (power factor) = 437.5VA or 0.4 kVA. If you have 8 devices in one rack, you would get a total load of 3.2kVA.

For this estimation of 3.2kva, how long does it last for ? Just a rough estimation and doesn't stick to any UPS models.

Thanks
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"10 to 15 minutes backup for the rated load", for rated load, are you talking about my estimated kva (provindg this esimation = actual kva consumption).

Can I say if I have 2 x 3.2kva sustained power supply time will be 30min ?

Thanks
Yes, for sure.

If you connect the "two 3.2 KVA UPS with 10minutes" in Parallel, it means you have "6.4 KVA with 10 minutes".

While you use 3.2 KVa load on this, it will give you double time!!!


Since your load is only 3.2 KVA, using 2x3.2KVA is useless, because the devices still will be drawing 3.2KVA. Instead, use 1x3.2KVA and expand the battery(If you have no plan to increase the load in future).

But if you already have 2x3.2Kva UPS, it can be connected together to get 6.4KVA for 10 to 15 minutes, which in turn gives 20-30 minutes when you use the load of 3.2KVA.

Note: Please check the documentation of your UPS on how to connect two UPS in parallel.

Hope this helps.
One more thing, it is always recommended to use a UPS atleast 20% more capacity than the estimated load.
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For a UPS in paraell, are you telling about connecting the UPS together and function as a single logical UPS ?

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You can't connect UPS in parrallel....

You have to buy one with the appropriate up-time.

Unless you split the servers between UPS....
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