7pin charging everything?

Susan Premo

Super Active Member
Nov 5, 2020
1,039
Minnesota
Is it true that while connected to the 7 pin and towing our aliner that it's only charging the DC? I don't understand too much about this, so I'm trying. Hope this is the right place to ask this question. Thanks.
 

Raycfe

Waterford Ct.
Oct 3, 2007
18,436
Waterford, Ct
Some simple facts. ......... the outlets in your camper only work when plugged into "Shore Power". (which just like a big extension cord).
The 7 pin connection "can" supply ......... only 12 VDC (battery power) because that's all your car has. And to add many cars/trucks only supply 12 Vdc power if they are wired for it ........... and then may only do so with the key on.
And because the charging system in your car/truck job is to keep its battery charged, its needs come first ........ and may never fully charge a camper battery.

The difference between VAC voltage and VDC volt. is like the outlets in your house and a flashlight. You can't power your house with a flashlight. Hope this helps.
 

Susan Premo

Super Active Member
Nov 5, 2020
1,039
Minnesota
Yes, it does help me , I only really wanted it for our furnace in fall and fridge in spring/summer. Hoping to avoid having to buy a generator.
 

Susan Premo

Super Active Member
Nov 5, 2020
1,039
Minnesota
Fridge is a power hog so that's out go the question. The furnace yes if you use it sparingly. turn it on before bed, shut off during the night, on before you get up.
Ah, thank you. I suppose we'll have to buy a generator or I'd really like a solar set up, hmm. If I did end up with a generator what kind do most folks use, I know Honda is quiet, but they also cost$2,000.
 

xxxapache

Super Active Member
Jul 30, 2008
4,558
If you do not plan to ever use AC with a generator and only want to charge batteries and run lights, the Harbor Freight 1400 watt Predator Inverter is a good unit. It is quiet. It had an eco mode that even more quiet. Eco mode is designed to be used to charge batteries. I believe the 1400 watt Predator is on sale right now for $419
 

WimStang

Member
Jul 17, 2022
23
Hmmm...back from several days boon docking and used our fridge and furnace on 12v while doing so. I have a group 31 battery and my fridge only runs on 12v in the 2023 Aliner Ranger 12. We used the lights and did nothing sparingly or unusual. The longest part of the trip was 4 days running on the battery. The new type of fridge does not require much juice, after it is chills down. I brought a back up cooler thinking I would need it, but did not. I see your Aliner is older however you might want to see if your fridge will run on propane...also get a battery that is at least a group 31 deep cycle. Hope this helps.
 

jeepster04

Active Member
Nov 23, 2010
298
IMHO, the DC portion of the fridge is almost useless. It will hardly keep the fridge cold when hooked up to the TV and will still slowly deplete the battery on your camper while you're driving. Stop to eat? It will drain the camper battery VERY QUICKLY.

The TV will charge the trailer battery but it will charge it very slowly. Its not like using a battery charger or letting the converter charge the battery.

I was camping last week and noticed someone running their vehicle every morning, he was trying to charge his camper battery. For some reason he felt the need to turn his trucks headlights on, so the camper lights were all lit up like a christmas tree just sitting in his camping spot... Odd people out there. There is a way that you can use your TV to properly charge the camper battery, but it involves things you are mostly likely not interested in (called a DC to DC charger).

I've always left the furnace on overnight with no issues. You will need to charge the battery each day though.
 

Susan Premo

Super Active Member
Nov 5, 2020
1,039
Minnesota
Wold it help with running the fridge
If you do not plan to ever use AC with a generator and only want to charge batteries and run lights, the Harbor Freight 1400 watt Predator Inverter is a good unit. It is quiet. It had an eco mode that even more quiet. Eco mode is designed to be used to charge batteries. I believe the 1400 watt Predator is on sale right now for $419

IMHO, the DC portion of the fridge is almost useless. It will hardly keep the fridge cold when hooked up to the TV and will still slowly deplete the battery on your camper while you're driving. Stop to eat? It will drain the camper battery VERY QUICKLY.

The TV will charge the trailer battery but it will charge it very slowly. Its not like using a battery charger or letting the converter charge the battery.

I was camping last week and noticed someone running their vehicle every morning, he was trying to charge his camper battery. For some reason he felt the need to turn his trucks headlights on, so the camper lights were all lit up like a christmas tree just sitting in his camping spot... Odd people out there. There is a way that you can use your TV to properly charge the camper battery, but it involves things you are mostly likely not interested in (called a DC to DC charger).

I've always left the furnace on overnight with no issues. You will need to charge the battery each day though.
Thanks, I'll probably go with the less expensive generator, don't think we need a $2,000 one.
 

TSQ

Active Member
Mar 28, 2021
377
Niagara Region, ON
Use your fridge on propane as @Raycfe mentioned.

A DC-DC charger is pretty much required to get any decent charge off a modern vehicle as @jeepster04 mentioned.

I was camping last week and noticed someone running their vehicle every morning, he was trying to charge his camper battery. For some reason he felt the need to turn his trucks headlights on, so the camper lights were all lit up like a christmas tree just sitting in his camping spot... Odd people out there.
A lot of modern vehicles have a multi-stage battery charging profile - when the vehicle alternator drops down to float voltage (~13.2V) it won't charge the trailer battery. Turning on the headlights will usually cause the alternator to push the voltage back up to ~14.2V. A DC-DC charger, as you mentioned, will help alleviate this problem.

Ah, thank you. I suppose we'll have to buy a generator or I'd really like a solar set up, hmm.
Lots of portable solar options out there such as:

If I did end up with a generator what kind do most folks use, I know Honda is quiet, but they also cost $2,000.
Personally, if I went with a generator I'd probably go with a propane one - no gas to spill, no carburettor getting gummed up during storage.

There is a Baja/Ryobi one that makes 700W continuous, should run a 25A or 35A converter (or even a larger high quality charger with active PFC):

I've also seen a (slightly) larger ALP one that makes 850W continuous, should run up to a 45A converter (or 50A high efficiency charger):

I have no personal experience with either generator.
 
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JimmyM

Super Active Member
Gold Supporting Member
Jun 5, 2014
3,333
Franklin, MA
Definitely figure out how to run your fridge on propane. On the 12V setting it will draw about 10amps continuously. If your fridge is already cold, you can use the 12v setting to keep it from getting warm, but you NEED to be religious about turning it on ONLY when plugged into your TV with the engine running.
I recently installed a DC-DC charger in my camper to keep things topped up while driving. Its a 14.5V @ 15A model. It puts out a full 14.5V at 15A when the TV is connected and running. There's no way I would get that sort of current into the camper without it.
They're pretty cheap too. Mine was $50 on AliExpress
 

Econ

Super Active Member
Aug 18, 2019
1,573
Deep South
Wold it help with running the fridge
I'll probably go with the less expensive generator, don't think we need a $2,000 one.
I have been a big Honda Fan for over 40 years. The 2200 ie is not $2000. Without shopping I found one for 1199.99. Ther is another that is smaller and costs a little less.

Considering Harbour Freight is $400.00ish and how much use it is worthy of consideration.

I boondock a lot. I'm mainly set up for propane, refrig; Generator, cloudy days. solar panel for the CPAP and general 12 volt. Do not run the refrig and have the 7 pin at the same time
 

bruce wayne

Member
Jun 16, 2020
43
i have a ranger 12, with a stock ac/dc/propane frig. i only use the 12vdc while driving. it will drain your rv batt in a short time, (for me, about 2 hrs), it can actually drain both batteries, depending on how your tv is wired. i use the propane all the time, except when at home cooling the frig, i'll use ac, prior to use. i have a harbor freight genny. it will run my ac all day long on about a gallon of gas. i did end up getting a renogy 100 watt solar suitcase too, i love it. it will keep your battery topped off, even in western pa, the land of clouds. my battery is able to run my furnace and lights all weekend w no probs.
 

bruce wayne

Member
Jun 16, 2020
43
the stock 6000 btu needs about 1300 watts on startup. my hf genny has plenty of juice to run non stop. its almost as quiet as a honda at about 1/3 the price. check out youtube comparisons.
 

Michael J

Active Member
Aug 9, 2018
201
Michigan
It does run on propane as well, thanks!
On propane it uses no power from the 12v system saving power, I would try to do some at home camping to see how everything is functioning and how it's works or if not able to do at home I would do it as close as possible in case you have to return home for something.
I personally use a check list I have on my cell that I can uncheck and use over and over and modify as needed
 

Chris4598

Member
Aug 6, 2021
16
Florida
On propane it uses no power from the 12v system saving power, I would try to do some at home camping to see how everything is functioning and how it's works or if not able to do at home I would do it as close as possible in case you have to return home for something.
I personally use a check list I have on my cell that I can uncheck and use over and over and modify as needed
I believe thatalthough the fridge works on propane it still uses some battery.
 




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