Question wire colors and specs?

[chaostactics]

So I'm putting in a Victron Multiplus and the wiring coming from the shore power inlet needs to be extended to reach it.*

The current shore power enters from the back of the RV and gets to my main distro/breaker panel midway through the trailer.

The multi plus is mounted in the front cargo passthrough.

I have run 10/3 wire (3 conductive wires and a ground) from the Multiplus to the main distro/breaker panel. And was planning on splicing it into the preexisting shore power wiring to feed the AC in on the multiplus. (Unhook shore power from the panel and send it to the multiplus, which will send AC to the panel via a new run of 6/3).

The problem is, is that the shore power supply to the panel is single strand 12/2 (two conductives and a ground, i.e. bare copper and black and white) while the line to be spliced to the Multiplus is black, white, green: L, PE, N.

So when I splice them together I have a 12/2 and a 10/3... How do I match up the wires?




*I am not putting in a new shore power inlet nor am I going to run all new wiring from the shore power inlet to the Multiplus.

**I DO NOT HAVE A TRANSFER SWITCH.

*** The wiring diagram is from explorist, I did not design it.



Multiplus wiring.


Main distro panel



Terminal connectors for splicing shore power to Multipus AC in.

 

[CharlesinGA]

The problem is, is that the shore power supply to the panel is single strand 12/2 (two conductives and a ground, i.e. bare copper and black and white) while the line to be spliced to the Multiplus is black, white, green Black, Green, White: L, PE, N.

For the AC input Black is LINE, Green is PE - Protective Earth or simply Earth, White is NEUTRAL (exactly backwards from the DC world) Too confusing, forget it.

Your shore power should (almost for certain is) be 10/2 w/grd, not 12. If Romex, is it orange jacket? that is 10 gauge. 12 gauge is white Yellow, 14 gauge is blue White.

In any case, you connect white to white, black to black, and green to bare copper.

Edit: looking at your panel closely, yes, your shore going to the 30 amp breaker is the largest wire, the 20 amp for the A/C is clearly smaller but the remainder are even smaller. Very easy to see on your ground bar, large 10 gauge at the left, 12 gauge on the far right, 5 different 14 gauge in three terminals. Yes it is OK to pair ground wires of the same size in a single hole/set screw. It is NOT OK to pair white neutrals in a single hole in the bar.

Charles

 

[Contributor]

Don't get confused with your set up. You only have a 120 VAC circuit, not 240 VAC. In 120VAC, there are only two conducting wires, the line (L) and the neutral (N), the green wire (PE) is the ground, it does not conduct. It is there for safety and reference.

I have run 10/3 wire (3 conductive wires and a ground) from the Multiplus to the main distro/breaker panel.

You don't need 3 conductive wires, you only need 2. The Colored wire (black) is the line (L), the white wire is the neutral (N) and the green is the earth ground (PE). If you have an extra wire, either rerun a different wire or just cut off the extra one.

 

[OldWEB]

I have been scratching my head over what it is you are actually doing. The AC wire sizes are all over the place, not making sense for a "normal" inverter setup, I do understand you have solar.
But if your shore power is #12 wire, by code you are NOT allowed to splice in (or use) a larger sized wire.
Why is it you have #12? That is only 20 amps max. I did hear you say that you were NOT going to run new wire to the shore outlet, but that may be the only way... IF the outlet is rated for #10 amperage.
What is the AC IN amperage?

 

[chaostactics]

I have been scratching my head over what it is you are actually doing. The AC wire sizes are all over the place, not making sense for a "normal" inverter setup, I do understand you have solar.
But if your shore power is #12 wire, by code you are NOT allowed to splice in (or use) a larger sized wire.
Why is it you have #12? That is only 20 amps max. I did hear you say that you were NOT going to run new wire to the shore outlet, but that may be the only way... IF the outlet is rated for #10 amperage.
What is the AC IN amperage?

@CharlesinGA corrected it. My shore is 10/2 not 12/2. It's orange jacket Romex.

 

[chaostactics]

Don't get confused with your set up. You only have a 120 VAC circuit, not 240 VAC. In 120VAC, there are only two conducting wires, the line (L) and the neutral (N), the green wire (PE) is the ground, it does not conduct. It is there for safety and reference.



You don't need 3 conductive wires, you only need 2. The Colored wire (black) is the line (L), the white wire is the neutral (N) and the green is the earth ground (PE). If you have an extra wire, either rerun a different wire or just cut off the extra one.

You're right I misspoke. Not 3 conductor wire. It's 3 straded wires white, green, black, plus a bare copper ground.

 

[Gary RV_Wizard]

Not 3 conductor wire. It's 3 straded wires white, green, black, plus a bare copper ground.

Still confused. What sort of cable has both a green insulated wire and a bare copper?

 

[chaostactics]

Still confused. What sort of cable has both a green insulated wire and a bare copper?

The wrong kind when you ask for 6/3 and don't pay attention, again. 100% my fault. I should have known after the first **** by a big box store.

What I ended up with was 6/3 black, white, red, bare copper. I brought back the stuff they sold me before that was stranded, stranded, solid copper. And I told him all 3 wires need to be stranded (because the guys on the RV forums said I do). So he gave me a wire that technically has 3 stranded wires.

All so much talk about "needing" stranded wires only to find that 96% of the preexisting wiring in the trailer is Romex or similar.

At some point I'll probably consider replacing the 6/3 I have with some that's W/B/G but for now all I have to work with is what I was sold. No where nearby has W/B/G stranded 6/3 and I'm already 2.5 days behind on a time sensitive departure.

Red stranded will be used as ground right now until I can get some W/B/G. I'm the only one who will be accessing my electrical and I will mark my wire as to what is being used for ground.

Very very expensive lesson learned. ****

 

[Contributor]

Get some green electrical tape and wrap some around the ends where the connections are made. That will make it to code and tell others that it is a green wire, don't sweat it, it's OK.

 

[OldWEB]

All so much talk about "needing" stranded wires only to find that 96% of the preexisting wiring in the trailer is Romex or similar.

It is your casa, you can do what you want, but as you found out Romex is cheaper than stranded wire... hence the reason the RV builders use it. You will not find solid wire in a automobile, tractor trailer, airplane, even a locomotive, but an RV could sit for 96% of its life and you may get by with solid wire. I just know of many instances of overheated (solid) wire connections, most in the main panel, then in the receptacles of RVs.
On the slide portions of our RV, stranded cable has been used for the shorter runs.

 

[Knobs]

OK, maybe someone can educate me. On the solid vs stranded issue in RV wiring... why?

It is my understanding that:

• Solid is cheaper, lower resistance, lower capacitance, (i.e. lower attenuation), higher current-carrying capacity (for the given gauge), and more resistant to corrosion and adverse weather conditions.
• Stranded is more flexible, so easier to run the wires, and better in applications where there will be continued flexing (such as car doors, etc.).

So, why is stranded preferred in RV AC wiring for those who want to "do it right"?

 

[Larry N.]

Check out your second bullet point, especially the second half...

 

[Knobs]

Check out your second bullet point, especially the second half...

The OP is wiring in a combined inverter and charger. None of those wires should be flexing.

Light fixtures, etc., in a slide out? Sure. Main wiring in an RV? Not so much.

But, the recommendation to use stranded wiring seems to be a blanket statement for how to do it right everywhere in the RV. It seems to me that solid's advantages make it best for much of the wiring in an RV.

If the normal functioning requires regular flexing of the wiring, use stranded. Otherwise, use solid.

Why is that not correct?

(I'm not making a declaration. I'm no electrician. I just don't understand.)

 

[Contributor]

When wiring circuits using conduit, stranded is the only way to go. Exposed Romex is not applicable for locations where scuffing is possible. There is no need for stranded wire in protected spaces in an RV. If I was going to run some wiring under the frame of an rv, then conduit is the way to go. Inside, behind paneling, Romex is fine. I'm talking about AC here, not DC. For DC, wires are routed in all manners in tight spaces and flexibility is a must for routing, not for reliability.