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 Post subject: Rounding issues in Table 130.4(E)(a) of 70E-2024
PostPosted: Tue Sep 26, 2023 2:16 am 

Joined: Tue May 22, 2012 12:08 am
Posts: 29
I'm a little confused about the rounding applied in Column 3 (Limited Approach Boundary - Exposed Fixed Circuit Part) of Table 130.4(E)(a) in 70E-2024, especially in the light of Column 2 metric values being corrected (i.e. rounded up) from 3.0 m to 3.1 m for an imperial value of 10 ft 0 in. in the latest edition.

In particular, I'm referring to the values for the voltages ranging from 50 V to 5 kV, which are all given as 1.0 m (3 ft 6 in.).

Attachment:
NFPA_70E_2024_Table_130.4_E_a.png
NFPA_70E_2024_Table_130.4_E_a.png [ 355.16 KiB | Viewed 7046 times ]

If I convert 1.0 metre to its imperial equivalent I get approximately 3 ft 3 in.
If I convert 3 ft 6 in. to its metric equivalent I get 1.0668 m, which rounded to 1 d.p. would be 1.1 m.

I have traced the value back to NEC Table 110.26(A)(1) using the references given in Annex C.2 of 70E-2024, but am curious as to whether the metric or the imperial value is the original value?
Attachment:
NFPA_70E_2024_AnnexC_C.2.1.3.png
NFPA_70E_2024_AnnexC_C.2.1.3.png [ 123.57 KiB | Viewed 7046 times ]

Attachment:
NFPA_70_2023_NEC_Table_110.26_A_1.png
NFPA_70_2023_NEC_Table_110.26_A_1.png [ 65.99 KiB | Viewed 7046 times ]


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