CPAP, tent camping & extension cords?

[Geer1]

Most outdoor plugs have GFCI protection. It is a requirement in the USA and in a rainy area like that I would be surprised if the plugs aren't already GFCI protected.

It is still a good practice to take precautions though because GFCI's don't always work. The main part of extension cord is safe unless sheath is damaged and conductors are exposed. The only area to worry about is each end where connections are made. If you keep these connections dry (don't lay on ground for example) then they will be fine and safe. That is why I recommended a single length cord ran into tent where it will stay dry vs using 2 short cords and an exposed connection outside of the tent.

If the connection gets wet and isn't GFCI protected (or it doesn't work) then it might flip a breaker or might energize a small nearby area. It won't blow up your CPAP or anything like that, you just might get a shock if you try to grab the connection out of the puddle.

[SideSleeper]

I will add my 2 cents on using a good heavy duty extension cord! My husband uses the 12 volt battery system in our travel trailer for his CPAP (I use a portable battery) when we don't have power. The first cord we tried wouldn't work-too lightweight even though it was a DC cord-- but everything is fine with a heavy cord even though it is pretty long. I would think the same applies when using the remote AC power.

[mesenteria]

The CFI is a good idea, especially in inclement weather, and especially if there's a chance your machine could be subjected to inordinate moisture or groundwater.  However, you should be safe since your only connection to the unit is with a plastic hose.

Secondly, your concern shouldn't be amperage but voltage.  Your machine will only draw what it needs in the way of amperage, probably less than 4 amps.  But it needs a range of voltage since the fan motor is a DC motor and will vary its delivery volume by getting voltage that is metered from an issuing controller.  If your blower motor needs to deliver a lot of volume for some reason, it will require more voltage.  If the extension cord is too long, and too thin, the voltage reaching your machine may be somewhat less than the engineering calls for.  If your extension cord is going to be in the 16-14 gauge range, and less than 60' or so, I don't believe you need to worry.

[RNeil]

I am an electrical engineer who just returned from a camping trip with my grandson. The camp site was typical of all Virginia state parks. It had a box with two circuit breakers, 30 and 15 amps. The 15 amp breaker was for a duplex 120 volt receptacle with built in ground fault interrupter protection. North Carolina state parks have a similar system where they have electrical service. GFCI has been required for all outdoor 120 volt receptacles since about 1972, so you don't need to bring your own. I used a 50 foot extension cord. I also had a 12 foot cord, but it was too short.

You might also see facilities with a 20 amp breaker, which is fine. The CPAP will need about 1 to 4 amps, so you don't need to worry about the cord being too long or too thin. I can't imagine needing more than 50 feet. Be carful about trip hazards.

I put less water in the humidifier because it was not quite level. Except for that and the extension cord, it was just like using CPAP at home.