Buncha dumb generator questions

[Vantair]

If not already stated, the standard stock converter chargers can be VERY S..L..O..W..........original constant voltage / charging models would take 8-12 hours to bring a battery bank back to life. Check you converter model to verify what you have.

Much better as one stated to either get a “smart” multistage portable charger (50.00-80.00) that can run off the Gen 120v. Clips direct to the battery terminals at a far quicker charge pace so a 1-2 hour stint would equal 6+ hours from the standard built in converter charge speed or if towing.

Saves Gen time, noise, gas and healthier for the battery.
(For Permanent install, Newer converter slip-in replacements such as the Progressive Dynamics PD4600 are smart 4 multistage lead acid, agm and lithium chargers and can adjust speed of Gen charging as well). Approx $225.00

[gypsydad]

Originally Posted by uncle_bob

Hi

This:

https://www.airstream.com/wp-content...-Airstream.pdf

Says you have a "2 way" fridge in your trailer. In simple English, it will run on 12V or 120V. It will not run on propane. The "old" propane fridges pulled about 1A on average. These newer models are up in the 3 or 4 A range. Indeed it varies a bit with the settings, outside temperature, and how often you open the door.

As noted earlier, with stock batteries, you have ~40AH range to "play with" when using brief runs of the generator to charge batteries. 40 AH / 4A = 10 hours. That would mean running the generator at least twice a day. Likely run time would be an hour or more each. An hour at breakfast and two hours at dinner seems like a reasonable approach.

At least in the campgrounds we have been in, "common courtesy" has prevailed. Running a *quiet* generator at meal time has been about all most folks have done. Even a 1,000W Honda will do a fine job charging the batteries.

To charge the batteries, the generator puts out 120V. That goes into your "shore power" inlet on the trailer. The converter / charger in the trailer turns that 120V into 12V to charge
the batteries. You typically see about 30A out of the stock charger. Thus the need to run for "at least" an hour.

So what can go wrong?

First up is the fact that looking at battery voltage is a really poor way to figure out how well the battery is charged. You will be "tuning" your run time to keep things topped up. Having a lousy "fuel gauge" makes this really tough. A shunt based battery monitor is a *much* better way to see what's going on.

Second up is (again as noted above) your usage probably includes more than just the fridge. We run lights some of the time. We pump water. We also run the fans for ventilation. Depending on how much of this you do, you could easily add 50% to your average drain. Turn on the inverter for a while and all bets are off .... ( = don't run the inverter !!! ).

Third, stuff happens. If you are depending on the generator to run several times a day, every day .... that's a lot. Run out of fuel or have some other random occurrence and there isn't a lot of time to recover. My preference would be for a setup that can run for at least a day (or two) "on it's own".

Other things you *could* do:

As some have mentioned, solar is a wonderful thing. Coming up with 30 to 50 AH a day is not all that crazy, under reasonable conditions. That would get you a *lot* more "run on it's own" time. The gotcha is a cloudy day or a campsite in deep shade.

Upgrade your batteries. There are a lot of ways to do this. The one I recommend is to go to lithium batteries. Simply swapping your two existing batteries would get you to 200AH of *usable* capacity. Effectively, you would have about 5X the "on it's own" time. Lithiums also charge much more quickly. That could shrink your generator run time.

Propane vs gas *is* a consideration when you buy a generator. Your trailer has propane onboard. With a "no propane" fridge, it's just sitting there most of the time. If the generator gets carried as a "just in case" sort of thing, not having to lug a can of gas is a plus. Even if you do have a 20 pound propane bottle for the generator, it will last a very long time. Gas in a 5 gallon can ... probably not so long life. Propane is very much "no muss no fuss" compared to playing with gas. Depending on where the generator is stored / hauled that can be a big deal.

Cost is always a concern on any of this.

A shunt monitor is just over $200. Solar likely starts in around $2,000 and goes up from there. Lithium batteries are around $1,800 for the batteries plus a couple hundred for other bits and pieces. Depending on what sales are running right now, a propane converted 2200i will be in the $1200 to $1900 range.

In our case, the answer was "all of the above". We have been out with the trailer for *many* months each year over 3 of the last 4 years. I would guess that half the time we are not hooked to shore power. I have yet to fire up the generator ..... ( Note: I *do* have a fridge that runs on propane and 400AH of lithiums. I also have a trailer that runs about 50AH a day, no matter what).

Bob

Once again, great suggestions from many of our experienced ASers here...Uncle Bob has covered most everything I would have suggested....note there are a few "die-hard's" also posting a "minimalist approach"; and thats fine, if your not wanting to invest in comfort. The wife and I appreciate strong battery power, the convenience of solar, and also the value of having a propane powered generator. In the Rockies where you mentioned you are looking to spend time in in the summer, you may want your AC a few times, but evenings are typically not warm enough to require AC like in some of the southern states. I have a suitcase GoPower 80W solar set up and just replaced my Champion 3400Dual Fuel with a Honda 2200 propane model from Genconnx. The solar tops off batteries most of the time depending on where we are camping, but the generator is of course, our lifeline while boondocking for a week or more...it has allowed piece of mind knowing it's there if/when needed to charge batteries. Sometimes, it can get cold in the Rockies, and you need heater...even in July!

In 18 years camping in MT over the summer May-Sept, I have used my AC only a few times, for a few hours max to cool down the AS, and that was 2 years ago while up around Glacier/ Hungry Horse camping...Forgot to leave the windows open during the day and it got a bit warm while we were away. The Honda2200 propane does just fine with the 15000AC and Easystart, if needed. Starts every time and is quiet. We use 6V Trojan batteries and have been pleased with their use/service model. I envy the Li batteries many have, but not ready to plunk down the extra $$ yet for that luxury...solar, generator, 6V Trojan set up is working fine..

[gypsydad]

Originally Posted by Vantair

If not already stated, the standard stock converter chargers can be VERY S..L..O..W..........original constant voltage / charging models would take 8-12 hours to bring a battery bank back to life. Check you converter model to verify what you have.

Much better as one stated to either get a “smart” multistage portable charger (50.00-80.00) that can run off the Gen 120v. Clips direct to the battery terminals at a far quicker charge pace so a 1-2 hour stint would equal 6+ hours from the standard built in converter charge speed or if towing.

Saves Gen time, noise, gas and healthier for the battery.
(For Permanent install, Newer converter slip-in replacements such as the Progressive Dynamics PD4600 are smart 4 multistage lead acid, agm and lithium chargers and can adjust speed of Gen charging as well). Approx $225.00

In 2018, AS replaced the "slow" single stage converter/charger system, which as many of us know, boiled our batteries to death.. They started including a 3 stage unit, and I have not seen any issues with this converter system? Think the OP has a newer AS, right? I know we replaced ours on our 2017 28' FC model, with a Boondocker 4 stage unit 3 years ago; it does a great job of charging and maintaining our batteries, like the PD you mention. Not sure the newer AS's having issues any longer with the 3 stage units that come with them now?

[ASFC25_2019]

Originally Posted by kelmech

Hi all,

I looked in the forums for these questions but couldn't find answers newer than ~10 years old so asking again. We're getting ready for a long RV trip in Wyoming and Montana and Colorado in various parks where we will have no hookups for up to 7 days in a row. We'll have water and dump stations enough to be fine.

We're deciding on a generator (likely the really quiet Honda inverter, DK model). Here are my questions:

1. What's protocol in parks? I know what hours we CAN run generators at each place, but, do people run generators for an hour or two or keep them on the whole day? Last time I did this was over 20 years ago and I remember them being really loud and obnoxious. My husband says they're not any more, but, what do most of you do? Do you keep them on as long as it's not quiet hours or what? For reference, the park where we will be the longest is the non electrical area of Gros Ventre in Grand Tetons.

2. I think the only power draw I am really concerned about is the refrigerator fan. I'll go showerless and hot waterless and we have plenty of blankets and warm gear to sleep in, and we’ll never camp without electricity where we would need AC, but, is it even possible to only have the generator on for a few hours and have the draw on the battery from the fridge not kill our batteries? What have you all experienced?

3. Do any of you regularly camp without a generator but using the fridge? (Is it possible we don't even need a generator?)

4. What else should we know that I haven't asked?

Thanks in advance for any answers. Excited for this trip!

Yes, we do travel with a Honda 2200 but do not have to use it very often. We were just had our Grand Canyon trip, and they only have a two-hour window to run a generator. However, we have installed an Expion360 DC to DC charger along with the external solar panel. Power is not an issue for us anymore. The DC to DC charger is https://www.expion360.com/shop/25amp...dc-charger.php

We were at Yellowstone last year and staying in the generator loop and were receiving complaints when running 2200. I just reminded them that we stayed in a generator loop but decided to install the DC to DC charger. Now we can just let our tow auto-idle, and we installed two for 50 Ah charge. It is amazing.

Yes, we also have the Expion360 battery upgrade for our Fly Cloud 25RB. Our issue is water shortage while dry camping, not power now.

[uncle_bob]

Originally Posted by gypsydad

In 2018, AS replaced the "slow" single stage converter/charger system, which as many of us know, boiled our batteries to death.. They started including a 3 stage unit, and I have not seen any issues with this converter system? Think the OP has a newer AS, right? I know we replaced ours on our 2017 28' FC model, with a Boondocker 4 stage unit 3 years ago; it does a great job of charging and maintaining our batteries, like the PD you mention. Not sure the newer AS's having issues any longer with the 3 stage units that come with them now?

Hi

Unfortunately, the "slow charge" is simply the way lead acid chemistry works. You can indeed speed things up by going up to 16 or 18V out of the charger. There are a number of chargers that do exactly this. I would not let any of them near an RV electrical system. In truth, I don't use them on any battery that is still hooked to a vehicle.

One very easy way to check out what's going on is with your shunt based monitor. You can watch the charge current into the batteries vs time. With Lithium's, the charger runs at full output pretty much right up to the end. You either have 80A into the batteries or you have nearly nothing. It's the "current taper" that you see with lead acids that is the slow down going on .... Current drops from max, but is still up there for quite a while.

With solar, does this matter? Not a lot. I certainly do *not* get 80A of charge current out of my solar setup. It's in a "taper" mode pretty much all the time. Low and slow is what solar does well. Ten hours to top things up? Not a problem for solar. If "full blast" is 10A, you aren't going to see much of a slow down as things top up.

Do we always take the batteries to zero? Hopefully not ( with any sort of battery). The more normal situation is to run from 20% down back up to full. You aren't going to spend all day running the generator to do that.

Fun !!!

Bob

[panamerican]

I have a Yamaha inverter generator, similar to the Hondas.

Mine has an LP conversion so I can tap right onto the onboard LP I already have with me.

I have boondocked for upward if 7-10 days and toward the end, was clearly showing signs of running out of power. I went with the 900watt because when boondocking, running a generator 24/7 for a A/C unit to me seemed kind of self defeating in terms of boondocking, but each person's needs are different.

The 7 way will charge the coach batteries, but don't expect anywhere near the power reserve that the on-board converter will provide or a direct 12v connection from the generator to the battery. The 7 way is a very slow, very low power xfer. I tried it years ago and results were marginal at best after running the truck for over 30 minutes. Running the Yamaha for the same 30 mins, either tied into the shore power line or directly connecting to the batter as a charger yielded far better results and more power stored.

[uncle_bob]

Originally Posted by Native143

I just picked the CarGenerator up at https://www.cargenerator.com. I love it because 1) it's lightweight 2) runs off my car's battery 3) quiet 4)no smell 5) it can run for an hour or two to top off batteries or run an appliance or two. 6) gas consumption is lower than a usual gennie. I don't plan on running it for hours but could, for example after a hurricane power outage. Since I don't have an inverter built in this works perfectly for me. Check it out.

Hi

I would be *very* careful with one of those things.

Like the "solar generator" guys, these folks seem to be a bit confused about what a generator is. Their gizmo is simply an inverter. It doe not "generate" any power.

Depending on your vehicle, the battery may be small or very small. It also is not a "deep cycle" device. (Yes you can optionally get big trucks with fancy battery setups ...). If you have a 80AH battery in the vehicle, that's doing pretty well these days. <40AH is not uncommon.

Since is't not a deep cycle battery, taking a vehicle's battery to half charge is not a good idea at all. You aren't going to be able to use 40AH off of the 80AH device.

Just as the batteries have shrunk, so have the alternators. (weight matters ...). If you run the engine to "feed" your magic inverter, there's only just so much current to do this or that. 1KW out means that it's pulling about 100A. That's a *lot* for a modern vehicle's electrical system.

If you *are* pulling 100A off of just the battery, figure that you have minutes (not hours, certainly not "70 hours run time") before you need to quit.

Assuming you don't fry the electrical system, you will find that the engine needs to be running above 1,000 RPM to get the alternator doing much of anything. Most "fast idle" setups get up around 1,500 RPM.

Idle (fast or otherwise) is not something your engine likes doing. You will wear stuff out doing a lot of idle. How much is a "that depends" sort of thing. Is moving your 200,000 mile engine rebuild point to 100,000 miles something that matters to you? Again that depends. It *is* going to cost somebody.

Bob

[uncle_bob]

Originally Posted by panamerican

I have a Yamaha inverter generator, similar to the Hondas.

Mine has an LP conversion so I can tap right onto the onboard LP I already have with me.

I have boondocked for upward if 7-10 days and toward the end, was clearly showing signs of running out of power. I went with the 900watt because when boondocking, running a generator 24/7 for a A/C unit to me seemed kind of self defeating in terms of boondocking, but each person's needs are different.

The 7 way will charge the coach batteries, but don't expect anywhere near the power reserve that the on-board converter will provide or a direct 12v connection from the generator to the battery. The 7 way is a very slow, very low power xfer. I tried it years ago and results were marginal at best after running the truck for over 30 minutes. Running the Yamaha for the same 30 mins, either tied into the shore power line or directly connecting to the batter as a charger yielded far better results and more power stored.

Hi

Charging RV batteries off of the 12V output from a generator is not a real good idea. The typical generator supplies a few amps at 12V. Running the 120 out of the generator into the converter / charger gives you a *lot* more current.

The math:

12V at 5 to 10 is a typical "charge output". On the same basis your generator is rated at 8A

https://www.yamahagenerators.com/Pro...QaAo2ZEALw_wcB

Your converter / charger is rated at 55A.

Your typical batteries are in the 150 to 200 AH range. If they are discharged more than a bit, they will accept quite a bit of current. Will you get the full 55A? Probably not. You also won't get the full 8A out of the generator under a lot of conditions. There's a bit of marketing in both numbers.

Your generator will use roughly the same fuel at any output level below around 1/3 output. The 8 x 12 = 96W on the charge output is *not* much of a load on a 2KW generator. 55A at 12V = 660W. Even that isn't pushing you much past the 1/3 point.

Hook the generator to the shore power input on the trailer. That is by far the best way to do it.

Bob

[panamerican]

Originally Posted by uncle_bob

Hi

Hook the generator to the shore power input on the trailer. That is by far the best way to do it.

Bob

I don't disagree and honestly connecting to the built in converter is far easier too. My comments were more to show options, and compared to the 7way, the 12v might still be a better option, but clearly nowhere near as efficient or convenient at just plugin 'er in.