RV Generators

[MountainMan]

I have a 13.5K BTU AC in my travel trailer. What should I look for in purchasing an RV generator large enough for the AC and to recharge the trailer batteries? What is an inverter? Is it important to have one on your generator? Any recommended brands and on-line stores?

[JSchuricht]

You need to find one that can handle the continuous current draw as well as the start up current. Keep in mind that unless you get a really large generator, you probably won't be able to run the AC and microwave at the same time.

An inverter is used to invert DC from a battery to AC which your microwave and air conditioner use. Many good inverters will also double as a battery charger, I recommend a Outback inverter if you don't mind the price premium. Basically, you would have the inverter connected to your batteries and shore power so when not plugged in you can run small loads or even large ones for a short time, ie the microwave for a few minutes. When the inverter senses AC power either from shore or the generator, it would pass the power on to your appliances and use the left over to charge your batteries. For a trailer, you will probably need a 12v inverter.

[wingnut]

we have a 5500 watt generator to run ours. you also have to have a 30 amp plug cause the 20 cant handle the surge of the AC kicking on and off

[SuperCrutyPS]

Originally Posted by JSchuricht

You need to find one that can handle the continuous current draw as well as the start up current. Keep in mind that unless you get a really large generator, you probably won't be able to run the AC and microwave at the same time.

An inverter is used to invert DC from a battery to AC which your microwave and air conditioner use. Many good inverters will also double as a battery charger, I recommend a Outback inverter if you don't mind the price premium. Basically, you would have the inverter connected to your batteries and shore power so when not plugged in you can run small loads or even large ones for a short time, ie the microwave for a few minutes. When the inverter senses AC power either from shore or the generator, it would pass the power on to your appliances and use the left over to charge your batteries. For a trailer, you will probably need a 12v inverter.

The first part I agree with....

The second part I'm a bit confused.

Most travel trailer's shore power cable brings AC into the trailer. Anything AC-powered runs off the Shore power. The trailers I've had already had an inverter in them to charge the batteries while plugged into shore power. The 12VDC circuits run off the battery(s) and do so whether you are plugged into shore power or not. The one part I do understand is that an inverter hooked to the battery(s) may allow you to run an AC-powered appliance for a short time.

A generator puts out AC power that the shore power cable can hook into. wingnut is right about needing a 30-amp recepticle. Most trailers (Unless they require a 50-amp service) have the 30-amp plug on the end of the shore power cable.

[JSchuricht]

Most trailers I have seen have a battery charger, not an inverter. The difference is the battery charger is just to charge the batteries from and AC source such as shore power or a AC generator. An inverter may be more common in the newer trailers, but from what I have seen is either aftermarket or part of an expensive package.

A good inverter can double as a battery charger. Either way, your 12v loads still run off the battery. AC loads will run off shore power, generator or battery via inverter. Don't plan on running a air conditioner off a battery via inverter it's cost prohibitive and the weight of the batteries required make it impracticable.

What you may have seen is some generators have a built in inverter. I think it's Honda that makes them. The difference in these generators is that the generators are producing DC, or possibly rectified AC, and inverting it to 110/220V AC. The advantage with this kind of generator is the output tends to be cleaner. Generators can do weird things, especially if their RPM starts to wonder from what the generator head is designed for.

With a traditional generator, for the US, you are outputting 60 cycles or 60Hz AC. This is important for things like old alarm clocks that keep time by counting the cycles and inductive loads like the motor in a refrigerator. (note most campers use a heating element rather than a motor) If a generator starts to vary it's RPM causing a change in the number of cycles per second, a clock could count fast or slow and a motor could burn out or trip the breaker.

A generator with an inverter creates it's own sign wave electronically and is less susceptible to a varying frequency. You will most likely be fine with either type of generator. The majority of generators do not use a inverter and have less components to go bad.

[tubular031]

I run my ac off my little 3500 Champ from tractor supply. They are usually $349 but if you watch them they often go on sale for $299. Runs my trailer, fridge and charger no prob. The only down side is that when its putting out 25 amps it gets pretty loud. Be careful of the people around you, they often camp to get awway from the noise and the world. Dont run your loud gen and disrupt that....

Now if you want to spend the big bucks, you can get an RV style gen and they will be very quiet. I was looking at them for a while but could not live with the 3k price tag plus install if you are not gen prepped.

[fourx4forfun]

from what i have heard, read and understand is the inverter does provide all your power when hooked up to shore lines and does charge your batteries if functioning correctly, i had a hilo that ran everything but the charging of the battery quit, so i just hooked up a trickle charger to maintain that and not replace the entire inverter, hello 20 versus hundreds.

[fourx4forfun]

currently i have a onan 4000 in my trailer from the factory, runs the frig, ac, lights n everything fine when its running good, right now thats an issue.

[tubular031]

your gen is not working? or not running right?

[DirtyDiesel]

Originally Posted by fourx4forfun

currently i have a onan 4000 in my trailer from the factory, runs the frig, ac, lights n everything fine when its running good, right now thats an issue.

wats it doing. we had a problem with our gen in our 40ft toyhauler. ended up taking it to the dealer and they said the carb was clogged up cuz of not being used. apparently the ONAN carbs hav a bunch of really tiny orifices that can easily get clogged up. they said it needs to be cranked at the very least, 1 every 2 weeks.

bak to the OP, our 5500 ONAN in our TH soesnt even seem to change a beat when the a/c kicks on. we can also do watever we need to inside. we've had the a/c on big flat screen going and the microwave on at the same time and all it does is skip a beat when a new load is added and it goes right bak to sounding jus the way it did.