12V Bus to 12V outlet to charge Laptops/Phones/Etc

I understand how to run wiring from my 120v bus to outlets for 120v products like a blender or tv.
When it comes to 12v thought I'm a little confused. If I have a 12v bus I get how to run a live & ground wire to a light & boom, light. But if I do the same concept but instead to an outlet with only a live & ground (no neutral), then connect a laptop & charger (which has a step down already), would that work? Would it take in the 12v & say hey I only need to step it down a little bit & work?

rafrojack said:

I understand how to run wiring from my 120v bus to outlets for 120v products like a blender or tv.
When it comes to 12v thought I'm a little confused. If I have a 12v bus I get how to run a live & ground wire to a light & boom, light. But if I do the same concept but instead to an outlet with only a live & ground (no neutral), then connect a laptop & charger (which has a step down already), would that work? Would it take in the 12v & say hey I only need to step it down a little bit & work?

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I'm not quite sure what you are trying to accomplish - If i'm understanding correctly you are wanting to charge a 12v laptop directly off of your 12v system?

Wired similarly, make sure you use a fuse or circuit breaker at the supply to protect the wiring.
Here's a panel I did for 24V DC and several circuits.

rafrojack said:

But if I do the same concept but instead to an outlet with only a live & ground (no neutral),

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12VDC only has a positive and a negative, there is no 'neutral'. You simply run two wires from the 12VDC source, a postive and a negative, and connect them to your 12VDC outlets (NOT an outlet that looks like a wall outlet). The only thing you can power are 12VDC items. Laptops can range anywhere from 9 to 24VDC, so you cannot plug directly in. If you have a 12volt charger made specifically for your laptop, then you can plug THAT in.

PHoganDive said:

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My OCDness gets a warm fuzzy looking at those crisp 90 degree bends.

But...<sigh>.... Cable Bending Rules

svetz said:

My OCDness gets a warm fuzzy looking at those crisp 90 degree bends.

But...<sigh>.... Cable Bending Rules

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There isn’t an issue with the rules.
#10 conductor is only 2mm diameter... times 8 will be 16mm... or about 5/8” so... unless that inner conductor bend radius is less than 16mm it is fine. To code that is...

Supervstech said:

There isn’t an issue with the rules.

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Are you sure? Not trying to challenge you, just want to make sure I understand.
A couple of the red wires at the top look to be 90 degree bends, not a "curved" radius. I'm thinking the yellow arrows, not the green ones...

svetz said:

Are you sure? Not trying to challenge you, just want to make sure I understand.
A couple of the red wires at the top look to be 90 degree bends, not a "curved" radius. I'm thinking the yellow arrows, not the green ones...

View attachment 421

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Yup.
The code for bending radius is to allow adequate room in panels and switchboards to be able to bend the wire and attach to the connections.
The rule is there so someone doesn’t try feeding 4/0 cable into a side entry panel and try to force the cable into a ultra tight bend breaker connection. The wire in the picture has tons of room, and is very organized.

The radius spoken in the code refers to the distance between direction changes... ya have to go to article 9 I think, get the conductor diameter, then multiply times 8 for single conductor, or times 12 for armored multiwire cables... a #10 thwn-2 cable is 2mm I think. I don’t have my code book on me. Say it is 3/16” diameter wire... times 8 would be 24/16, or 1-1/2” radius of a turn... that means a 180degree direction change in the wire needs 1-1/2” diameter bend to turn around.
A 90 degree bend is fine.

Picture a 200amp main panel with 4/0 cable coming in the bottom with main lugs on top of the box. The wire needs to turn 180degrees to feed the lugs. There needs to be 8 wire diameters for the radius of the loop in the wire to feed the lugs.

Thanks! Knowing the why makes it easier to interpret the codes!

svetz said:

Thanks! Knowing the why makes it easier to interpret the codes!

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Yup, years of combined classes and decades of dealing with inspectors helps to better understand the often INCOMPREHENSIBLE code entries...

svetz said:

Thanks! Knowing the why makes it easier to interpret the codes!

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Oh Yeh ...gotta interpret those codes properly yeh! They got a code for zip ties ? cutting I mean . I curse these clots who cut them at an angle and I cut myself on the ends.