I am an electrical dummy, and I need some help with this one.I realize that when plugged in at an rv site, my on board inverter (converter?) will charge my batteries. This year we have been boon docking quite a bit, and have been using our 2000W generator/inverter to run a few 120V things like a blender or hair dryer.My question....... when I have the generator hooked up and running to power the little stuff, should I hook up the batteries as well to charge them, or does it make any difference at all? I also carry a 12V separate charger which I can plug in to the generator and charge the batteries.My feeling is that the inverter on my generator might be better than the onboard unit.Thanks for your help.

Nope. That 2000w generator charger is only 8A. Your converter is 30A. Stick with the converter.

Let's start with a converter will charge your batteries from 120 volts and an inverter will use amps from your battery to give you 120 volts. If you plug your RV into your generator to use your hair dryer your converter will be charging your batteries at the same time. There is no need to use a separate battery charger. It will take 3-4 hours to charge the batteries depending on how much you discharged them the night before.

You will need to post the model number of the converter to get best answers. A few are great and most are duds. The portable might be fast if it is 20+ amps rated but post the rating so we have something to compare.

No need for a separate charger. As corvettekent said your RV converter will charge when the RV is connected to the generator anyway. If your generator has a built in 12v "battery charging" output and cord just ignore it. Pretend it's not there. They are useless and pointless. They put out very little power and it's poorly regulated at that.

use generator/inverter to charge batteries and power trailer

22 Replies

ssthrd
Explorer
Aug 20, 2020
Direct is good. I hate to guess. :)
Huntindog
Explorer
Aug 20, 2020
ssthrd wrote:
Cord is toast. Thanks for the advice. It started out as a quick fix and ended up as “normal”. I promise to be good from now on.

Great!
Would you believe that one of my titles at work is that of "Safety Coordinator?"

Most of the time it entails a lot of paperwork/computerwork, and persuading nicely of better ways to work safe.... Once in awhile though, something really dangerous is sighted by my radar, and I need to be VERY direct in order to get my point across quickly.

This was one of those times.

Often, this direct approach is initially met with anger/denial, but later turns into appreciation.

Glad you took it well.

Be safe out there.
ssthrd
Explorer
Aug 19, 2020
Cord is toast. Thanks for the advice. It started out as a quick fix and ended up as “normal”. I promise to be good from now on.
Huntindog
Explorer
Aug 19, 2020
ssthrd wrote:
This might sound dumb, but......

I don't have an adaptor to go from 110 at the generator to the 30 amp connection at the trailer, so I changed the female end on an extension chord to male and just plug it into the gfci socket on the outside of the trailer. Does the trailer know that power is not coming from the shore power line or not, and does the converter care at all?

What you have done is made what is called a "suicide cord" A very bad idea. Destroy it before someone gets hurt.

Do not fool around with electricity. Standard types of plugs, cables, etc. are made for a reason.... To keep everyone safe. Do not "invent" a different way of doing it.
time2roll
Nomad
Aug 19, 2020
ssthrd wrote:
This might sound dumb, but......

I don't have an adaptor to go from 110 at the generator to the 30 amp connection at the trailer, so I changed the female end on an extension chord to male and just plug it into the gfci socket on the outside of the trailer. Does the trailer know that power is not coming from the shore power line or not, and does the converter care at all?
Please throw that cord in the trash.
aka suicide cord or deadman's cord.

Amazon has the adapter you need.

Amazon

Walmart should have one also.
pianotuna
Nomad III
Aug 19, 2020
ssthrd wrote:

I do have 260 watts of solar, but I am in a bad spot for solar right now in the bush. I end up running the generator for a couple of hours a day. I was thinking that charging the battery at the same time with the inverter would be helpful, but from what I read, it probably doesn't matter. Looks like the onboard system might be better in any case.

The batteries are 2x 6 volt T105 Trojans. My issue might be that the batteries are getting weak. After charging for a couple of hours, I can get them to 80% or so every day, but just charging my iPhone, and nothing much else, the level falls to below 65%. My hydrometer shows weak batteries in all cells......

What you are seeing is called "progressive capacity loss". Get to a shore power connection and do a full charge followed by an equalization charge.

It is best to recharge to 100% as often as humanly possible--but certainly it needs to be done at least every 9 cycles.

Doing it on the generator may be more expensive than getting to reliable shore power. Freecampsites.net has a filter that allows you to select camprounds that have power. Some of them are even free.

https://freecampsites.net/
pianotuna
Nomad III
Aug 19, 2020
ssthrd wrote:
This might sound dumb, but......

I don't have an adaptor to go from 110 at the generator to the 30 amp connection at the trailer, so I changed the female end on an extension chord to male and just plug it into the gfci socket on the outside of the trailer. Does the trailer know that power is not coming from the shore power line or not, and does the converter care at all?

No, but what you are doing is not advisable.
ssthrd
Explorer
Aug 19, 2020
This might sound dumb, but......

I don't have an adaptor to go from 110 at the generator to the 30 amp connection at the trailer, so I changed the female end on an extension chord to male and just plug it into the gfci socket on the outside of the trailer. Does the trailer know that power is not coming from the shore power line or not, and does the converter care at all?
ssthrd
Explorer
Aug 19, 2020
pianotuna wrote:
Add a little bit of solar and the generator runs may be fewer. The battery bank will show you some love by lasting a lot longer.

I do have 260 watts of solar, but I am in a bad spot for solar right now in the bush. I end up running the generator for a couple of hours a day. I was thinking that charging the battery at the same time with the inverter would be helpful, but from what I read, it probably doesn't matter. Looks like the onboard system might be better in any case.

The batteries are 2x 6 volt T105 Trojans. My issue might be that the batteries are getting weak. After charging for a couple of hours, I can get them to 80% or so every day, but just charging my iPhone, and nothing much else, the level falls to below 65%. My hydrometer shows weak batteries in all cells......
valhalla360
Navigator
Aug 17, 2020
Assuming you are running the generator for an hour or two anyway to cover high demand loads...just plug into the generator and call it good.

The trailer doesn't know if it's connected to a pedestal or the generator.

The "converter" which is really just a battery charger (never understood why the RV industry made up a new term) will take the 120v AC power and use it to charge the 12v DC batteries.

Now if you continue to do a lot of boondocking and get into solar and large battery banks, you may want to consider a better converter and battery monitor system but keep it simple at first. If you do make the jump to an extensive 12v DC system, start doing an energy audit of what you use and for how long. This will allow you to determine you needs in terms of solar and battery bank size much more accurately.

Forum Discussion

use generator/inverter to charge batteries and power trailer

22 Replies

About Travel Trailer Group

Related Content

Inverter on Generator wiring?

Inverter Generator

Generator vs Battery/Inverter/Solar

Inverter Generators

Travel Trailer