Do the batteries recharge while towing?

[babock]

You use a voltage drop calculator to figure your voltage drop. Those tables that tell you what size cable to use for a given distance and current are only good if it also is based on a %voltage drop.


If you have a 15' run which is roundtrip 6AWG, you will get 0.15V drop at 14V @ 25A. That will probably work fine except that if your alternator is actually only putting out 14V, you won't be getting 25A to your batteries.

[Herk7769]

Originally Posted by babock

Of course unless you have a Progressive Dynamics converter with the Charge Wizard which is a 4 stage charger.

That's true, but my advice to use a dedicated charger hooked directly to the battery and running off the generator is still my first choice.

This Speed Charger is one of the best for this purpose:

https://shop.advanceautoparts.com/p/...00a/21280061-P

[extremebike]

I started boondocking a few years back and noticed that the Jensen radio goes into standby mode when on battery and consumes power. I do not get any radio stations where I camp so I put a switch on the power line to the radio. This required removal of the radio and some wire cutting and crimping but it's pretty straight forward.

[babock]

Originally Posted by Herk7769

That's true, but my advice to use a dedicated charger hooked directly to the battery and running off the generator is still my first choice.

If your converter is far away from your batteries and you have a lot of voltage drop,I would agree. However, that would be the first thing I would fix when I bought a new trailer, which is what I did. A converter right next to the batteries.


The problem with that Schumacher charger is that it is not a true 3 or 4 stage charger. There are many that are. In addition, if you have a large battery bank or AGMs, the Progressive Dynamics converters will charge the battery faster since that one is limited to 15A. With my Lithium batteries, my Progressive Dynamics converter delivers a full 60A to the batteries under generator power.


When I charge batteries under gen power, I want to run the genny as little as possible. 2 GC FLA batteries will take close to 25A if they are discharged. AGMs will take a LOT more. Why limit yourself with 15A?

[babock]

Originally Posted by extremebike

I started boondocking a few years back and noticed that the Jensen radio goes into standby mode when on battery and consumes power. I do not get any radio stations where I camp so I put a switch on the power line to the radio. This required removal of the radio and some wire cutting and crimping but it's pretty straight forward.

Yep...one of the first things I did. Takes just under 1A in standby which adds up in 24 hours. The switch I added to turn off the radio also turns off the 4 high power USB outlets I installed.

[mjwkayaker]

Purchased solar panel kit from Amazon along with an extra battery (2 batt total). Gray water tank filling up is my boondocking challenge now - even with the heat on every night.

[cadman99]

Solar Panels could work but if mounted flat they are at best about 65- 70% effective and you will need a minimum of two or three 100 watt panels and lots of sunshine.

I prefer a small generator and separate battery charger. Mount the charger in the trailer and wire it to the batteries. This gives you the option to run the generator in the truck bed (if you have a truck) while you are driving.

If you want the more complex method mount a second alternator on your vehicle with appropriate wiring.

[clarkbre]

On the topic of generators, if you can't stomach the price of a Honda or Yamaha, the WEN 56200i is a good, inexpensive inverter generator.

I looked in to the solar set up as well but the wooded areas we camp and Seattle liquid sunshine turned me away.

The 56200i provides up to 1600 continuous watts (plenty of power to charge the batteries) and is truly whisper quiet. While running in eco mode, you can stand a few feet away and have a normal conversation. I bought mine after reading tons of reviews and researching longevity on the motor. I also liked that customer service was US based and there was part support online. I purchased directly from WEN and it was $399 shipped, no sales tax. It has also proved to be useful around the house.

Just my $0.02.

[markjamestx]

Have to tell you all with the 21 Footers, that was our first and we loved it to death that had to move up to a 31 for more room for this old retired couple

[ependydad]

I happened to grab a screenshot of my Victron monitor from the truck the other day. I’m definitely not recharging while driving.

[FishinGuy]

Thanks for that screen shot !
Hopefully that will help those uncertain about how many amps are going to the back end of the truck then on to the TT batteries.
Hopefully they see it as about close to NOTHING.
Supply 120v from a generator or shore power and have a charger ( portable or built-in ) as close as possible to the batteries ( to avoid voltage drop ).
All of this info will certainly help others on the learning curve.
Thanks to all for your input.

[Alben]

I have a Thornwave Bluetooth Battery Monitor / DC Power Meter hooked up to my trailer battery. When going down the road, I have my 3 way fridge running on 12VDC. My Jeep Grand Cherokee is able to supply the necessary current for the fridge and slightly trickle charge the trailer battery. I know because the battery monitor is showing a small positive current going into the battery (<0.5Amp)

[babock]

Originally Posted by ependydad

I happened to grab a screenshot of my Victron monitor from the truck the other day. I’m definitely not recharging while driving.

Attachment 195122

Different subject...Kind of interesting your SOC says it's 98% and your voltage is only 13.27V. Have you not done a full charge in awhile to get it synced up to 100%? I know you have Battleborns. 13.27V should be more like 88%.

[rockfordroo]

If you have a Dometic fridge, it probably has a door heater. The heater pulls about 0.5 amps. Look on the schematic on the back of the fridge. Here's mine, the door heater is item K in the red box.



I've attached a document that tells you how to disable it while keeping the inside light working. If you don't mind losing the inside light, you can just pull the wire off of pin J2.

[babock]

Originally Posted by rockfordroo

If you have a Dometic fridge, it probably has a door heater. The heater pulls about 0.5 amps. Look on the schematic on the back of the fridge. Here's mine, the door heater is item K in the red box.

I did the same thing. Cut the wire near the light to disable the heater.

[johnleann]

Originally Posted by rockfordroo

If you have a Dometic fridge, it probably has a door heater. The heater pulls about 0.5 amps. Look on the schematic on the back of the fridge. Here's mine, the door heater is item K in the red box.

Attachment 195126

I've attached a document that tells you how to disable it while keeping the inside light working. If you don't mind losing the inside light, you can just pull the wire off of pin J2.

Isn't this the same as the switch above the door in the frame, that controls moisture or humidity in the fridge? I have switch on mine and was wondering if this is the same thing.

[babock]

Originally Posted by johnleann

Isn't this the same as the switch above the door in the frame, that controls moisture or humidity in the fridge? I have switch on mine and was wondering if this is the same thing.

If you have the switch, that's how you turn off the heater. Many, like mine, don't have it.

[bikendan]

Originally Posted by babock

If you have the switch, that's how you turn off the heater. Many, like mine, don't have it.

Yep, my 2007 Roo had a Dometic with the climate control switch in the frame.
my 2016 TT has a Dometic without the switch but still has climate control using 12v power. i unplugged the wire on the control board.

[rockfordroo]

Originally Posted by johnleann

Isn't this the same as the switch above the door in the frame, that controls moisture or humidity in the fridge? I have switch on mine and was wondering if this is the same thing.

Yes, but Dometic seems to have discontinued the switch sometime between 2010 and 2012, near as I can tell. Now it's on all the time. The OP didn't say what model year TT he has, but I assumed he did not have the switch.

If you have the switch, it looks like this:

[Halifax Jack]

Interesting topic. As a long time boater battery conservation is a must. The first thing I asked when shopping for a trailer was about the battery charger. All I got was a puzzled look. As mentioned I would invest in a smart charger with the highest charge rate affordable. Many have a sensor that measures battery temp so as to not overcharge. Like the mention of a #6 wire from truck battery as 7 pin connect will do not much more than trickle. Also amp hour meter is desirable. Think of it as a gas gauge for your batteries. The best generator in my opinion is one that is NOT running and solar is not what it is cracked up to be refer to amp hour meter. Solar will supplement and extend your stay boondocking but will not fully charge not unless you have several panels and are in the south where sun angle is higher. A high amp wire from front of truck must be properly fused locally. If you don't abuse golf carts that is less than 50% they will last over 10 years. 2 would give me 4 days on the hook with fridge running and LED lights. Certainly a topic that I will be investigating further

Cheers