2023 NEC Table 220.42(A) Note

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jes25

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"The 125 percent multiplier for a continuous load as specified in 210.20(A) is included, therefore no additional multiplier shall be required when using the unit loads in this table for calculating the minimum lighting load for a specified occupancy."

I don't understand this note. The 125% multiplier in 210.20(A) is for the conductor and OCPD of a branch circuit. I don't see how this has anything to do with calculated loads of a feeder or service which is what 220 Part 3 is about. Is it saying I don't need to add the extra 25% when I determine the quantity of the branch circuits I need for lighting?
 
210.20(A) is for branch circuits. 220 Part 3 is for calculating services and feeders. Maybe I don't understand the issue here
 
So the note is just saying: when you are calculating the quantity of lighting branch circuits required you don't need to add the extra 25% continuous load factor.
 
When using that table for your lighting load they already included the continuous loading factor of 125%. It was probably added because some jurisdiction would require the multiplier for feeder calculated loads when the table already included it.

Hence 220.42(B)(4) tells you when using efficient lighting calc you need to include the 125% factor for continuous loading.
 
wwhitney said:
FWIW, the note is deleted from the 2026 NEC Second Draft without changing any of the table values.

Cheers, Wayne
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But the panel statement for that second revision said:
Lighting loads were updated in the 2020 code and are appropriate based on the change approved. The note with the table is confusing and while it does identify the continuous nature of these loads, the fact that these are considered continuous should not be considered the sole reason for the 125-percent multiplier, refer to the Informational Note for 120.5(E). The note in table 120.42(A) is removed to clarify that the table values are not to be adjusted by 125-percent for continuous loading.
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In general the 125% adder does not apply to load calculations. It is used for branch circuit and feeder conductor and OCPD sizing.
120.5
(E) Percent Multiplier.
Load calculations shall not require continuous loads to be calculated at 125 percent.
Informational Note: A 125-percent multiplier could be required for reasons other than continuous load. Continuous loads impact the sizing of the conductor and OCPD but might not influence the load.
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What are the other reasons in 120.5(E) note?
"A 125-percent multiplier could be required for reasons other than continuous load"

"Continuous loads impact the sizing of the conductor and OCPD but might not influence the load." In what case does 125% influence the load itself?....not the conductor, not the OCPD. Where would I apply 125% to the load itself. My only guess is motor outlets...
 
don_resqcapt19 said:
But the panel statement for that second revision said:


In general the 125% adder does not apply to load calculations. It is used for branch circuit and feeder conductor and OCPD sizing.
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Thanks Don I understood the 125% not to apply to load calcs as well and was the spirit of my original question. Similar to the question I asked above, why the qualifier "in general" in your statement?
 
don_resqcapt19 said:
But the panel statement for that second revision said:
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Not really following the panel statement's reference to the IN for 120.5(E). For a lighting load, the topic of (renumbered) 120.42, what other reason would there be to apply a 125% multiplier? For that matter, are there any examples of the IN other than motor loads?

Anyway, seems to me the deletion of the note to (renumbered) Table 120.42 represents an increase in the minimum lighting load by 25%. E.g. say an area comes out to a lighting load of 10,000 VA per the table. Under the 2023 NEC, you know that figure includes the 125% continuous use factor, so if you want match the table, you'd install 8,000 VA nameplate of lighting, and if the lighting is a continuous load as is likely, your branch circuits and OCPD would be sized to 10,000VA. While under the 2026 NEC Second Draft, the equivalent would be to install 10,000 VA nameplate of lighting, and your branch circuits and OCPD would be sized to 12,500 VA.

BTW, in the 2026 NEC Second Draft, 120.42(B)(4) is clearly in conflict with 120.5(E).

Cheers, Wayne
 
jes25 said:
Thanks Don I understood the 125% not to apply to load calcs as well and was the spirit of my original question. Similar to the question I asked above, why the qualifier "in general" in your statement?
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only because I am not sure that there is not some rule that I missed
 
wwhitney said:
Not really following the panel statement's reference to the IN for 120.5(E). For a lighting load, the topic of (renumbered) 120.42, what other reason would there be to apply a 125% multiplier? For that matter, are there any examples of the IN other than motor loads?

Anyway, seems to me the deletion of the note to (renumbered) Table 120.42 represents an increase in the minimum lighting load by 25%. E.g. say an area comes out to a lighting load of 10,000 VA per the table. Under the 2023 NEC, you know that figure includes the 125% continuous use factor, so if you want match the table, you'd install 8,000 VA nameplate of lighting, and if the lighting is a continuous load as is likely, your branch circuits and OCPD would be sized to 10,000VA. While under the 2026 NEC Second Draft, the equivalent would be to install 10,000 VA nameplate of lighting, and your branch circuits and OCPD would be sized to 12,500 VA.

BTW, in the 2026 NEC Second Draft, 120.42(B)(4) is clearly in conflict with 120.5(E).

Cheers, Wayne
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The (B)(4) language needs to be written as an exception so it can modify 5(E). The CMP does not trust the energy codes, so it adding a 25% cushion to the energy code load.
 
don_resqcapt19 said:
The (B)(4) language needs to be written as an exception so it can modify 5(E). The CMP does not trust the energy codes, so it adding a 25% cushion to the energy code load.
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All they need to do is change the wording in 120.42(B)(4) to a 125% factor not identified as a continuous loading factor. Which is the case if it's really a "we don't trust the energy code" factor.

Another example is the 125% factor in 120.87(2) on determining existing loads by monitoring. That's a "we may have missed the peak current" factor, or a "peak current may have lasted less long than the averaging interval" factor, or a "all the other load computations are bloated, so we need something extra to be less dramatically different from the calculated load" factor.

BTW, the new language in 120.87(2) is dangerous. It now reads: "The maximum demand at 125 percent plus the new load minus any removed load determined in accordance with Article 120 Parts I, III, and IV does not exceed the ampacity of the feeder or rating of the service." To the extent that the observed load from monitoring per 120.87 is much less than the calculated load would be under Part III/IV, taking credit for the calculated load of the removed load, rather than requiring the load to be removed to be monitored separately, is a non-conservative overestimate of the load reduction.

Cheers, Wayne
 
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