Cisco power supply and APC UPS question

Question

Good afternoon, I am running a 4507 with the Power Supples PWR-C45-2800ACV
http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps4324/product_data_sheet09186a00801f3dd9.html
Can I plug this power supply into this UPS unit?
http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=SMX3000RMLV2UNC&tab=models

Answer 1

Jason:
My guess is that 2800w power supply is looking for two legs of AC in to make the DC stable on the switch.   I've installed a lot of 45XXx over the years but I never have more than 100 ports of active POE on them as most buildings have lots of computers and printers and a few VOIP phones and access points.  
Now, those power supplies are pretty fault tolerent and well built.  They can take (probably) swing voltage from 40-240V and 50-60Hz.    You can wire up the L6-30 into the TWLK cable and only have 20A of 120V on one leg from the output of your UPS.     You just have a single 30A hot, neutral and ground and a dead leg for hot into the power supply.   You use half the power supply.  
The capacitors on the power supply will just have to absorb that and deal with it.   That's their job.  Short term batteries. 
One thing you need to realize is that you don't have to have two full-capacity 2800w circuits for the switch.   The 2800 is a reference number and that's based on a lot of inneffiencies in the entire system.  
You've got at max a 2800w load and either 1 or two power supplies will feed it.    Two power supplies will be slightly less efficient than one but you're not pulling 5600w.   
If you could, answer the questions above on the number of POE devices you've got and we can work a solution to solve the power to the switch and to your nodes.  
You've got a lot of expensive, quality gear and the best solution isn't always to double up and re-buy what you've got.  
I am going to recommend a metered PDU so that you can watch the amperage as when you approach the limit of what your wires can haul, you need to pay attention to the national electric code.
If you can PM me, do.
-Luke