220.14 (A) vs (L) for PDU at server rack

[Anonymous785463]

Since active equipment is typically not included in the scope of work in design documentation. Is using 220.14 (L)(2), which allows for 180VA per 1 ft. of multi-outlet assemblies acceptable per code?

To be clear about my intent. I was provided an equipment list from the IT team, I know this equipment is not at 100% efficiency. Specifically speaking I feel comfortable taking at least a 80% demand factor on the equipment because I have seen the existing PDU meters showing values for peak demand at around 30%. Since I know the equipment being installed am I required to use 220.14 (A)? I feel showing 220.14 (L)(2) is sufficient in providing enough capacity for the PDU as a whole. What checks and balances does the inspector or plan check really have in enforcing 220.14 (A).

How can I as an engineer use the code to provide a VA that is not extremely excessive. All the meter readings I see end up being between 30-35% of the continuous load per the manufacturer. I feel like I am over engineering every piece of equipment.

Any thoughts or better loopholes to use? Can I take the VA and multiply by the manufacturer's efficiency to get a more accurate VA?

Thanks.

 

[Smart $]

This question is one of conscience.

Keep in mind the maximum current that a PDU will draw in use, at any time... not the average or most common demand. In your description you first say 30% peak demand, then later you stated 30-35% continuous use. I have to wonder if and how much you are fudging the numbers... so we're right back to the question being one of conscience...

Exactly what are you accomplishing by not using 220.14(A)?

Are you aware that you can use a value higher than 180VA per receptacle [220.14(H), (I), and (K), but not for 220.14(L), 2014 NEC edition]?

BTW, what year cycle are you using that there is an (L)(1) and (L)(2)? There are none as far back as 2005, and prior the requirements were in 220.3.

 

[zbang]

This is entirely a single reference point- I have some server cabinets in a data center each with a 30a 3-ph PDU where all equipment is fed 208v. Some of the full cab's sit around 20-24a per leg. I've also seen cab's with two PDUs and special cooling.