Introduce 415/240 V as a standardized voltage

wwhitney said:
Well, I submitted an identical PI. : - ) I guess the CMP preferred the wording in the substantiation to PI 2916, as that's what they borrowed for their change.

Cheers, Wayne
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They applied the same FR, FR-7992 and the same panel statement for both PI 2916 and PI 3129. I just took the first one when I looked at the PIs for 120.5
Public Input No. 3129-NFPA 70-2023 [ Section No. 220.5(A) ]

(A) Voltages.
Unless other voltages are specified, for purposes of calculating branch-circuit and feeder loads, nominal system voltages of 120, 120/240, 208Y/120, 240, 347, 416Y/240, 480Y/277, 480, 600Y/347, and 600 volts shall be used.

Statement of Problem and Substantiation for Public Input
416Y/240V is an increasingly common voltage system, for example in data centers that supply information technology equipment that requires 240V single phase. As such it deserves the standardization for calculations that inclusion in 220.5(A) would provide.
Submitter Information Verification
Submitter Full Name: Wayne Whitney
Organization: [ Not Specified ]
Street Address:
City:
State:
Zip:
Submittal Date: Tue Aug 29 14:14:44 EDT 2023
Committee: NEC-P02
Committee Statement
Resolution: FR-7992-NFPA 70-2024
Statement: Many industrial and commercial facilities, such as data centers, now use a 416Y/240 volt system. Adding this as a standard voltage to Article 220 assists users of the Code when performing load calculations for these systems.
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wwhitney said:
Well, I submitted an identical PI. : - ) I guess the CMP preferred the wording in the substantiation to PI 2916, as that's what they borrowed for their change.

Cheers, Wayne
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I looked at the minutes for CMP 2 for the first draft and the two PIs were "bundled" and acted on as a single PI. That is common when there are multiple PIs asking for the same thing.
 
hokadof188 said:
We are all seeing it in datacenters. It makes sense in offices and industry. In some cases, it's very easy to retrofit 277 by tapping the transformer low, though that usually falls to the utility.

Dare we offer it for residential consumption, like the majority of other developed nations?
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While at an IAEI meeting maybe ten years ago somebody told us two things about new voltage systems designers were proposing . 1) increase standard 480 volt three phase systems to 575/334 volts AC. that would save money by being able to use smaller wire and 2) install 120 volt DC panels on every floor of offices. It could save at least 3% energy and no need for a rectifier & guessing simpler power supplies In every computer, UPS'S, and other electronic devices. Would also save money on Sumer cooling.I was hired in 1970 towards the end of converting over a hundred two phase motors over to three phase. Was difficult finding real estate to mount new three phase panels. Would have two gangs working from Friday afternoon to Monday mornings ( 12 to 14 hour shifts ) to perform change overs. Company was replacing all of the old two phase chillers & ammonia compressors with three phase and other new equipment.
 
Jraef said:
And make everything 120V instantly obsolete? Yeah, that dog ain't gonna hunt...
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I thought it was impressive it only took Korea Electric Power Company (KEPCO) thirty-two years to completly raise the distribution voltage from a 100V system like Japan to 220V 60hz.
KEPCO began the switch in the early 70's and unscrewed the last 100V lightbulb in 2005.

Birken Vogt said:
The reason for 240/416 is that in the USA, 240 volt equipment is common, while 277 volt is less common and gets more exotic. Your existing computer and shaver can run on 240 but 277 would be too high.
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Yeah 277V is what an economist would call a 'weak path dependency' it was not widely adopted as expected, many 480 systems went to a delta configuration, Canada leaned towards 600Y347, South America did not widely adopt it, so it got left behind by the telcom / main frame server power sector, which became the data center world of today. It stretched the upper voltage band needed for a PSU adding cost, unlike 208V which is easy to support in the 90-265V range.
 
tortuga said:
I thought it was impressive it only took Korea Electric Power Company (KEPCO) thirty-two years to completly raise the distribution voltage from a 100V system like Japan to 220V 60hz.
KEPCO began the switch in the early 70's and unscrewed the last 100V lightbulb in 2005.


Yeah 277V is what an economist would call a 'weak path dependency' it was not widely adopted as expected, many 480 systems went to a delta configuration, Canada leaned towards 600Y347, South America did not widely adopt it, so it got left behind by the telcom / main frame server power sector, which became the data center world of today. It stretched the upper voltage band needed for a PSU adding cost, unlike 208V which is easy to support in the 90-265V range.
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A friend go mine did a lot of electrical work a for a bitcoin mining operation in my area...they simply ran the 240 volt mining machines at 277 volts without issue.
 
don_resqcapt19 said:
A friend go mine did a lot of electrical work a for a bitcoin mining operation in my area...they simply ran the 240 volt mining machines at 277 volts without issue.
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I've seen 277 flourescent fixtures operate on 240 with no issues.
 
ron said:
Most IT equipment is listed up to 250V. Your friend may not follow nameplates
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Yeah thats what I have encountered, and Telcom / ISP / data IT companies tend to be more on the particular end of the spectrum, particular up there with hospitals, things like voltage specs are very exact, I'd be more willing work a little outside of spec for say a welding / machine shop.
I herd about a small UPS contractor that won a bid to provide a 48VDC backup system for a rack of data equipment that ran off that, he neglected to notice that it had to be positive grounded -48VDC. Turns out thats a show stopper he from some reason could not switch the leads due to grounded cases, his whole plan had to change and he lost money on the job.
 
ron said:
Most IT equipment is listed up to 250V. Your friend may not follow nameplates
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The owner does not care about nameplates...just mining coins. The use of 277 was specified by the owner and the final connections to the power panels was by the owner.
 
don_resqcapt19 said:
The owner does not care about nameplates...just mining coins. The use of 277 was specified by the owner and the final connections to the power panels was by the owner.
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We run into that a lot, where the client may say to do something irrespective of whether it is code compliant or not. I am not willing to put put my name on the line, so I politely walk away and let them bully someone else.

We typically get asked back when something bad happens.
 
Besoeker3 said:
What equipment would use that for?
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North American consumer electronics are all typically designed to accept a nominal voltage anywhere from Japan 100V to Australia 240V 50 or 60 hz, Line - line or Line to Neutral, our old friend 277 did not get invited to the party becasue she was too high but sometimes we can sneak her in.
 
tortuga said:
North American consumer electronics are all typically designed to accept a nominal voltage anywhere from Japan 100V to Australia 240V 50 or 60 hz, Line - line or Line to Neutral, our old friend 277 did not get invited to the party becasue she was too high but sometimes we can sneak her in.
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Yes, I have travelled extensive - mostly on industrial systems. I just didn't recall the 100-280V. I may have in the past.
 
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