Do Derating conductors for 12vdc apply?

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d1reyad

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hi guys i ran 16awg wire for 12vdc led strip for under Cabinet an ect now my question i know with Ac current you have to derate to 70% if you have 8 CCC together or bundle MC when strapping so if i were to strap all my LV 12vdc wires together witch total in 26 conductor would my wire capacity decrease base on NEC code?
 
d1reyad said:
hi guys i ran 16awg wire for 12vdc led strip for under Cabinet an ect now my question i know with Ac current you have to derate to 70% if you have 8 CCC together or bundle MC when strapping so if i were to strap all my LV 12vdc wires together witch total in 26 conductor would my wire capacity decrease base on NEC code?
Click to expand...

I would think so:

Table 310.15(B)(3)(a) Adjustment Factors for More Than
Three Current-Carrying Conductors in a Raceway or Cable
 
i figure that since i just check back and it said 0 to 2000volt what article talk about bundle wires together like in a panel or for a certain distance where derating doesn't apply
 
yes they are class 2 i ask a license electrician and he said this doesn't apply to dc current and he is very knowledgeable when it come to code
 
Well now you can teach him something, he doesn't know it all. Chapter 3 does not apply to CL1, CL3 and CL2 circuits unless there is something in Art 725 that refers you to it. Accordingly, only Class 1 circuit conductors are subject to 300.15 & 300.17 derating- see 725.51.

And AC or DC makes no difference.

-Hal
 
Lets say for now that this was not class 2 wiring, but was still 12VDC. You would have to consider how much load each conductor is connected to. Since they are connected to LED's the amount of current is probably pretty low and it is unlikely you will create much heat in these conductors because the load is likely well below the ampacity of the conductor to start with, so deration may be necessary but will not result in increasing the conductor size.
 
hbiss said:
If it's not CL2 what is it? It can only be CL3 or CL1. Saying it's 12VDC means nothing. If it's CL3 no derating is necessary. If Class 1 then, yes 300.15 and 300.17 applies.

-Hal
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You saying it is impossible to have 12VDC from a non limited power source, or at least a source that meets the limitations of CL 2 or 3?

Take a good sized 12V battery and short the output with a piece of 16AWG and see how hot it gets.
 
hbiss said:
Well now you can teach him something, he doesn't know it all. Chapter 3 does not apply to CL1, CL3 and CL2 circuits unless there is something in Art 725 that refers you to it
-Hal
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I thought it was article 300, not Chapter 3.

725.3 Other Articles. Circuits and equipment shall comply
with the articles or sections listed in 725.3(A) through
(J). Only those sections of Article 300 referenced in this
article shall apply to Class 1, Class 2, and Class 3 circuits.
 
jumper said:
I thought it was article 300, not Chapter 3.

725.3 Other Articles. Circuits and equipment shall comply
with the articles or sections listed in 725.3(A) through
(J). Only those sections of Article 300 referenced in this
article shall apply to Class 1, Class 2, and Class 3 circuits.
Click to expand...

Nevermind......................:slaphead:
 
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