Adding a 12v outlet

[DNW]

I'd like to add a 12v "cigarette lighter" style outlet to the bedroom for a CPAP so we don't need to run the inverter at night.

Any tips, tricks or guides that I could refer to before I go tearing stuff open? I assume there is 12v relatively nearby since there are USB charging ports. Ideally, I'd like the outlet in the console between the twin beds...

TIA!
DNW

[field & stream]

Don’t know much about your trailer, but you might be able to replace your existing USB ports with a combination outlet containing both USB and cigarette lighter.

[nelsonh]

All of the machines I've seen (family members) are 110v. So I presume a 12v version exists, or maybe a dual voltage version? Just curious is all. In many (all?) of the twin bed trailers, the DC junction box is under the driver side bed, so you could run a circuit from there.

[DNW]

Originally Posted by nelsonh

All of the machines I've seen (family members) are 110v.

I assume you're referring to the CPAP.

As most small portable appliances, they generally run on 12v DC, and come with a "brick" that converts 120-240v AC to 12v DC.

[BGClassic]

I ran mine directly to the 12v gray box. Outlet and fuseholder are on the road side of the bed, so the run just goes to the front storage locker, where the 12V box resides. Tied directly to the battery buss, with the inline fuse. I used 12GA wiring.

My CPAP came with a buck converter that converts 12V to 24V, with the cigarette lighter plug. Saves battery when off-grid.

[GOUSC]

Originally Posted by BGClassic

I ran mine directly to the 12v gray box. Outlet and fuseholder are on the road side of the bed, so the run just goes to the front storage locker, where the 12V box resides. Tied directly to the battery buss, with the inline fuse. I used 12GA wiring.

My CPAP came with a buck converter that converts 12V to 24V, with the cigarette lighter plug. Saves battery when off-grid.

I did the same in my 27’ Globetrotter. Just find your circuit breaker panel. There should be a vacant 12V fuse slot and find a way to pull a wire to where you need the outlet, or close by.

[Doc Foster]

Originally Posted by DNW

I assume you're referring to the CPAP.

As most small portable appliances, they generally run on 12v DC, and come with a "brick" that converts 120-240v AC to 12v DC.

That is correct (former Cpap tech)

[greghoro]

My trailer has factory installed reading lamps under the overhead cabinets at each corner. I installed cigarette lighter receptacles next to them by tying into the reading lamp circuit, which has sufficient gauge wire.

I believe I used a 1” hole saw to accommodate the receptacle and accessed the wiring by removing the radio speakers in the same vacinity.

Greg

[TedSz]

I obtained an extra 12v cord for my CPAP and cut off the cigaretter lighter plug. I then popped out the USB charging jack near the bed and tapped into the 12v feeding that charger port with the bare end of the new cord. In my AST tapping into the line involved simply pulling out the center console drawer and splicing into the 12v line there. There was sufficient gap between the rear of the cabinet and the AST wall to easily slide in the cable. No holes to drill, no jack to buy.
Now there is a CPAP cord always powered and waiting for the CPAP to plug in. This is also more secure as it can't pull out of the cigarette jack in the night. When travelling the AC adapter and the regular 12v cord stay stowed in the carrrying bag.

Ted
2023 FC 23FBT

[bholland]

You'll want to make sure the wiring supporting the CPAP is of sufficient gauge, especially if you're repurposing a USB outlet.

If you have a travel CPAP, it might be fine. But if you're running a humidifier and/or heated tube, you'll be using much more current—probably several times the amperage a USB connector supplies (which I believe is typically 2a).

Cheers,
Bill

[BGClassic]

Originally Posted by bholland

You'll want to make sure the wiring supporting the CPAP is of sufficient gauge, especially if you're repurposing a USB outlet.

If you have a travel CPAP, it might be fine. But if you're running a humidifier and/or heated tube, you'll be using much more current—probably several times the amperage a USB connector supplies (which I believe is typically 2a).

Cheers,
Bill

Exactly. That's why I spec'd out a cigarette lighter jack from Blue Sea Systems, and fuseholder, and used 12GA wire. Once and done. The manual lists current draw specs as well.

I have had enough electrical issues with this Airstream, didn't want to create more.

[TedSz]

Be aware that the fusing and wire gauge of the 12v line feeding the USB charger is much larger than the USB charger's output current capability.

My 2023 FC23FBT has a 12v line feeding the USB charger fused at 15a and uses AWG 14 wire. My CPAP draws a maximum of 6⅔ amps even with the humidifier turned on.

The use of a cigar lighter port originally designed to heat an element to light a cigarette is a compromised and not physically secure way to power 12v devices.

In summary, while a USB charger port might take about 10 watts to provide 2a @ 5v, the circuit in my trailer, which I'm using to power my CPAP could supply up to 180 watts. My CPAP uses a maximum of 80 watts.

Secure hardwiring to the CPAP cable is the best approach.