Sizing question

[BillP]

I'm looking at buying another UPS and bouncing between another Symmetra or a Smart.

I thought I had a clue what I was doing until I looked at our existing Symmetra and got myself all confused.

Our Symmetra is a 6K with 3 power modules and 4 batteries.
I look at the website and it tells me the output is 34% of the Watts in both N+0 and N+1 (23% of the VA). And it's going at 6.7Amps.

I know enough to know that just because my server says it has an 850W power supply doesn't mean it will actually pull that much - so in saying that.

We have a 6509 in it with a 1300W power supply (the 6509 reports it's using 706 watts at 16.8A).

A 6509-E with a 6000W power supply (reports 1936W at 46.1A).

And 3 servers each with an 850W power supply.

Running with what I know (the Cisco equipment) I should be pulling at least 2642W (63% of the Symmetra max) at 62.9A (well above the 6.7 the Symmetra is reporting).

Every once in a while (once a month in the dead of night) I get a notice that the Symmetra spikes for 2 seconds over capacity. I'll buy into that if it is really running in the 80% usage all the time... but not 35% all the time.


Anyone have a clue what I'm missing?

[BillP · Accepted solution]

I'm looking at buying another UPS and bouncing between another Symmetra or a Smart.

I thought I had a clue what I was doing until I looked at our existing Symmetra and got myself all confused.

Our Symmetra is a 6K with 3 power modules and 4 batteries.
I look at the website and it tells me the output is 34% of the Watts in both N+0 and N+1 (23% of the VA). And it's going at 6.7Amps.

I know enough to know that just because my server says it has an 850W power supply doesn't mean it will actually pull that much - so in saying that.

We have a 6509 in it with a 1300W power supply (the 6509 reports it's using 706 watts at 16.8A).

A 6509-E with a 6000W power supply (reports 1936W at 46.1A).

And 3 servers each with an 850W power supply.

Running with what I know (the Cisco equipment) I should be pulling at least 2642W (63% of the Symmetra max) at 62.9A (well above the 6.7 the Symmetra is reporting).

Every once in a while (once a month in the dead of night) I get a notice that the Symmetra spikes for 2 seconds over capacity. I'll buy into that if it is really running in the 80% usage all the time... but not 35% all the time.


Anyone have a clue what I'm missing?