Wiring Question

norwood

I want to add a 12v accessory outlet and the closest wires are 10 AWG. The accessory outlet looks to be 18 AWG. Can I tap the larger wire? If so, what method is recommended?

Horigan

You can tap into the larger wire.  I would get a yellow butt connector sized for the 10 AWG.  For the 18 AWG wire strip a longer section of wire so you can fold it over and pinch it so it will fit into the yellow butt connector snuggly.  Get a quality ratcheting insulated terminal crimper.  Make sure it's for insulated connectors verses heat shrink connectors, which are slightly different.

This is the crimper and wire stripper I use.
https://www.amazon.com/gp/product/B08VVX6PWJ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

norwood

Thanks @Horigan. This is very helpful.

RTWCTS

Edit: when I reread the original post I realized the larger wire size mentioned was 10Gauge. A WAGO won’t work on a wire that large. Sorry for sharing poor information…

I've started using WAGO connectors @norwood. They can be used to join wires from12-24 Gauge, in either 12V or 120V applications. I think they'd be perfect for the splice you're looking to do. No more worries about mismatched wire sizes slipping out of a wire nut. NuCamp now uses them in the T@Bs too.

You can find them at most hardware stores or even on Amazon.
WAGO 221-413 Lever-Nuts 3 Conductor Compact Connectors 500 PK: Amazon.com: Industrial & Scientific

Horigan

Wago would be a good option.  You can trim some of the strands on the 10 AWG to make it effectively a 12 AWG to fit the Wago connector.

rfuss928

Horigan said:

Wago would be a good option.  You can trim some of the strands on the 10 AWG to make it effectively a 12 AWG to fit the Wago connector.

OR a better solution - you could buy the larger WAGO lever-nuts that fit 10awg. 

https://www.amazon.com/221-613-LEVER-NUTS-Conductor-Compact-Connectors/dp/B085ZQKQD2/ref=sr_1_7_sspa?crid=11JLKI73TW3N6&dib=eyJ2IjoiMSJ9.qLn1sGhuOUUPqskpd8XRGalNQnWQioUYkcTQCag4Q2xZoHXChyNIfeLyg14PPxRokjn4e0EJ1WFeO429RqvB5WAHb1u3gzavlYwnlCbvNAEaNnAoVajP_Fkdo6u8_WGCno2nfSCtA26VN3k3SaC6_1AVOH9pndwQy74Uu6Z0Q7LQoEiwxVIZ-oxACDmaOQH1VsFHmPEcAeLoY9HTGpf0MOLIqVooAdNV74JVGCvpwwWA7esHjmr0R3GCIrZEvsyuwn6YBbjQZKNbglMCr-OGXClTz8RN1LCBTfw4jZlbr1Q.ij4_dvX_Z3V0D_eD39AKMMrd3tWkCkgx_jDXUUmrXlU&dib_tag=se&keywords=wago+221-613&qid=1712540440&s=industrial&sprefix=wago+221-613,industrial,378&sr=1-7-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9tdGY&psc=1

You should make sure you know which circuit you are tapping.  The 10 awg is a 30 amp circuit.  Possibly the refrig or solar.  The 18awg is possibly a 7.5 amp fuse for the lights or LP detector.

Horigan

@rfuss928 Yeah.  I realized after posting that the 10 AWG insulation wouldn't fit into the smaller Wago connector.

ScottG

rfuss928 said:

...
You should make sure you know which circuit you are tapping.  The 10 awg is a 30 amp circuit.  Possibly the refrig or solar.  The 18awg is possibly a 7.5 amp fuse for the lights or LP detector.

rfuss928 makes a good point, with some potentially important implications you might want to consider (if you haven't already).

First, an 18awg wire tapped into a 30A circuit will not have adequate fuse protection. While the likelihood of that wire getting overloaded under normal circumstances is extremely small, you might consider installing a separate smaller fuse directly on the 18awg branch.

Second, every device or accessory you add to a circuit potentially increases the loads on that circuit. If that 10awg circuit is serving something important, make sure the additional loads won't exceed the main circuit's capacity.

Hammick

I have no experience with WAGO connectors but I do see NuCamp used them in our '23 TB 400.  You could also use a yellow Positap.  They are wonderful and no need to cut any wires.  I use them for accessories on my motorcycles.  When I go to see the bike the accessories come off and there is not damage to the wire.

https://www.amazon.com/Posi-tap%C2%AE-Connectors-10-12-Gauge-Wire/dp/B00389GGN0

Denny16

Connectors like Positaps are OK for low load connections, like for a light.
But for a larger load device like the 12v accessory outlet, you need a terminal strip type connection, like the Wago.  If you are installing a 12-volt power point connector (cigarette lighter type plug) you need one with a rating to match what you want to plug into it.  The 18AWG connector seems a little small for anything other than a light or small accessory battery charger (phone or tablet device).
cheers