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DC Color Codes via NFPA 79 1

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Ric111

Electrical
Aug 4, 2005
3
Having read every post on color code I can find in these forums hasn't answered my question.

NFPA 79 14.2.3.2 (1) states " White with Blue stripe for Grounded (current carrying) dc circuit cunductor."

Given a power supply (switching) is wired to 120VAC and the neutral is Grounded externally. If the power supply is internally connecting the output (24VDC) return to gnd is the White with Blue a requirement.

My contention is that the power supply is not floating and the DC return is connected to ground so the White Blue is required.
Their contention is that if the DC return is not directly connected to GND via a separate ground wire then the wiring should be all blue as per 14.2.4.3(3)

Whose right?

 
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Seems to be a gray area there (no pun intended)!!

Issues of this nature that split hairs between one persons interputation and anothers should be settled, in my opinion, by the end user and/or whomever is going to have final acceptance/complience of the pertinent equipment.

In the preface of NFPA 79 it gives an address to send any questions to:
NFPA Headquarters
Attn: Secretary, Standards Council
National Fire Protection Association
1 Batterymarch Park
P.O. Box 9101
Quincy, MA 02269-9101

David Baird
mrbaird@hotmail.com
Sr Controls Designer
EET degree.
Journeyman Electrician.
 
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