I suspect that 30a is insufficient

[Garyasml]

Please let me know if I am overreacting. Been RVing for 14 yours in 2 fifth wheels with 50amp service. I am looking at a 25' AS with only 30 amps. I am concerned that I will be underpowered. If I have the air conditioner on and somebody revs up the microwave while the toaster or coffee maker is on, I will blow breakers.
I have been to various campgrounds over the years where only a 30amp was available and have experienced this first hand. I can accept this on a $40k trailer but I expect more of a much more expensive airstream. Am I wrong to wonder why 50 amp isn't standard on such expensive trailer's. Even without a 2nd A.C., 30 amps seems insufficient.

[waninae39]

30a is plenty enough in a 25' AS 1 aircon can run with the uwave on
50 is only need to run 2 AirCons at the same time

[GOUSC]

I like 50A myself but some people are fine with 30A. Just look for one that has 50A as an option. I would think that option is available, especially if you have 2 A/C’s.

[Garyasml]

Please excuse my newbie ignorance, but what is "uwave"?

[S1njin]

I’ve never had a 50 amp coach before, so forgive my ignorance but I’m glad this topic came up.

In all my years of 30 amp, it boiled down to ‘you can run 2 big things’. AC, microwave, blowdryer, etc.

So, does 50 amp mean ‘I can run 3 big things’? Both ACs and the microwave, blow dryer, etc.?

[Garyasml]

In my experience with 5th wheels you have two choices ( I am not an electrician, so correct me if I a misunderstand):

1) 30 amps, 115 volts

2) 50 amps, 240 volts. In essence you have 2 separate circuits each with a capacity of 50 amps, 120 volts. Therefore you have 3.3 x the electrical capacity. 1 AC runs off each circuit giving you 35 amps available on each circuit for other appliance's.

[S1njin]

So .... I completely misunderstood the value of moving to 50 amps aside from being able to run 2 AC units.

[AgBullet]

Originally Posted by S1njin

I’ve never had a 50 amp coach before, so forgive my ignorance but I’m glad this topic came up.

In all my years of 30 amp, it boiled down to ‘you can run 2 big things’. AC, microwave, blowdryer, etc.

So, does 50 amp mean ‘I can run 3 big things’? Both ACs and the microwave, blow dryer, etc.?

Yes. Both A/Cs, microwave, etc. 50 amps provides fairly unconstrained use of electrical appliances including 2 A/Cs. I have a 27 GT, but if I was choosing a 25', I would still opt for 50 amps.

[jeffmc306]

Originally Posted by S1njin

So .... I completely misunderstood the value of moving to 50 amps aside from being able to run 2 AC units.

Depends on how you look at it; you get three circuits on 50A x2 so a lot more flexibility with 50A service compared to a single 30A with all circuits on one main.

[S1njin]

Thanks guys. Really pleased with my 50 amp option upgrade than !

[DKB_SATX]

Originally Posted by Garygosse

Please excuse my newbie ignorance, but what is "uwave"?

The lowercase Greek letter mu (μ) is used as shorthand for "micro" but may be hard to access on a keyboard. So I suspect it was intended to be μwave.

[DKB_SATX]

Regarding the topic of the thread, "horses for courses" comes to mind as a good enough reason. There are some lucky people who rarely camp where they even need air conditioning, and if you're not running the AC you'd have to really load up every available circuit to capacity to trip a healthy 30A campground breaker.

I made an intentional choice to get find a 30A single-AC version of my trailer, because I know the only camping I'm going to do here in Texas in the hot season is the night I have to stop between here and decent weather, and I got 2 Fantastic Fans instead of 1, a second shore-power inlet near the hitch and lighter more-flexible shore power cord. I have tripped a campground breaker once in 7 years, when I forgot the electric water heater element was on while the AC was running full tilt and I put something in the microwave. Yes, there are limits, but there are benefits as well.

This is apocryphal, but I have read a report (here on AIRForums) of someone being forced by a campground to move to a different campsite because they were using a 30A-to-50A adapter in a 30A site when the weather was cool and they weren't planning to use AC anyway.

[Thiss]

30amp only will pop our breakers if running two electric heaters.

However, now that we got a descant dehumidifier that blows warm air, we rarely use the electric heaters anymore winter camping.

[ROBERTSUNRUS]

Hi, My 30 Amp trailer has worked just fine for us for close to 20 years. I have had a few times that in cold weather my shore cord froze and I didn't want to break it trying to roll it up. I put my frozen shore power cord in the shower stall to defrost so I could roll it up and put it where it belongs. I would not want to fight that Anaconda of a 50 Amp cord in any weather.

[richard5933]

Originally Posted by Garygosse

Please let me know if I am overreacting. Been RVing for 14 yours in 2 fifth wheels with 50amp service. I am looking at a 25' AS with only 30 amps. I am concerned that I will be underpowered. If I have the air conditioner on and somebody revs up the microwave while the toaster or coffee maker is on, I will blow breakers.
I have been to various campgrounds over the years where only a 30amp was available and have experienced this first hand. I can accept this on a $40k trailer but I expect more of a much more expensive airstream. Am I wrong to wonder why 50 amp isn't standard on such expensive trailer's. Even without a 2nd A.C., 30 amps seems insufficient.

We have a 25-ft Airstream with only 30a service and have never had a problem. Could we though? Yes - if we intentionally ran everything all at once then we could.

For us the limiting factor with running all the electrical devices you've mentioned isn't the available power, it's the available counter space in a 25-ft trailer. Microwave, toaster, & coffee maker all at the same time implies lots going on in a tiny kitchen all at once. Maybe it's just the way we do things, but the coffee is done long before we get to the rest of all that.

We have a soft-start installed on our a/c unit, which also helps a lot with not having problems popping the main breaker. It has reduced the start-up load on the a/c enough that we can run the microwave and converter at the same time as the a/c without issue. If we were going to be running a toaster as well I'd probably flip the switch on the converter to make sure we didn't have a problem.

For us the ease of hooking a 30-amp trailer vs. lugging/storing the heavier cord is worth the minor inconvenience of sometimes having to think about how much power we use.

Remember, it's all about the "Principle of 7"

https://www.youtube.com/watch?v=WGPMadwqPKQ&t=25s

[Bill M.]

I expect the OP is correct, I do not think 30 amps will be enough for him and his style of camping. We also have 30 amp units and find that just not camping in really hot conditions is the best for us. So to the OP, if you buy an Airstream get one of the 50 amp models with 2 AC's. We have skipped fixing dinner because we did not want to turn off the AC to use the microwave. I am just fine with that. I expect the OP might not be from what he said. I just turned off a space heater to use the coffee pot and microwave this morning. I would probably buy another 30 amp model if I was going to get another AC. Used to the lifestyle. Do not want to camp in the really hot spots for long anyway.

[Garyasml]

Thanks to all for their input.

[Greenjeans]

I've assumed 30 vs 50 choice was bases on 1 vs 2 AC units. In Texas if your unit gives you a choice of 1 or 2 AC I would choose the 2.

Kinda like weight of the unit determines number of axles.

I've always camped in a smaller unit, one AC=30amps, never an issue.

Not sure if my assumptions are correct?

[Merlintiaga]

One nice use of two ac units is the ability to rapidly dehumidify on muggy days (like when it’s raining) when the temperature is too low for AC. I put one zone on AC and the other on heat (heat pump mode). In 15 minutes I can have the humidity down. You can only get two ac units with 50 amps. I’m guessing in an older trailer that does not have one thermostat that controls both the furnace and AC you can probably do this as well.

[uncle_bob]

Hi

As noted above, you go from 30A at 120V to 100A at 120V when switching from a "30A" hookup to a "50A" hookup. You have just over 3X the amount of power to "play with".

Since current is the limit here and power is what you use on most devices, this quickly gets a bit crazy. If the campground is supplying you with 120V, your 10A of drain is 1,200W. If (as some do) the campground is supplying you with (yikes !!!) 104V, you now need to pull 11.5A to get the same amount of power into your load.

Depending on outdoor heat, indoor temperature, and the humidity, your A/C can pull a range of currents. Put it in heat pump mode and the numbers likely go up a bit. Might it get up to 18A? They certainly can.

If you go to 100% of the 30A feed (you typically would aim for 80% or 24A), 18A into the A/C leaves you with 12A. If the microwave pulls 15A, that's a problem. The fridge probably is pulling some power and there might be lights on. You don't really have all of that 12A anyway ....

So, can you pop a 30A breaker? Yup, you most certainly can. There are lots of combinations that will do it. Hair dryers are a common culprit.

Can you go pretty much forever and ever with 30A and not pop breakers? Yup, you can do that as well. You just need to be a bit aware of what's what and manage it. A lot of folks get to the point they don't even think about what they are doing as they manage these loads.

Do 30A breakers trip right at 30A? Nope, some are defective and they trip early (or late). Even in good condition, you have to get a bit above 30A. Depending on a breaker to tell you what you what's what is *not* a good idea. Power plugs and cords do *not* like over current. They heat up by I^2 x R so twice as much heat at 1.4x the current. If the target is 24A (that 80% rule), that's going to be 34A.

If this really bugs you, move up to a trailer that has two A/C's on it. You then get a 50A service tossed in "for free". You add the load of that A/C, however the power available goes way up. It's only money .

Fun

Bob