Charging Toad in transit

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carson

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Has anyone devised a method of charging/maintaining the battery while (whilst) in transit?

The parasitic (unwanted) battery drain during long hauls kills my battery. First I pulled the fuse for the radio, then I installed a battery disconnect switch (knife switch), both of which are not desirable over time. The switch idea worked great, but within a year the switch corroded badly to and became unstable. (The contact areas were too marginal to sustain starting current over time).

I would like to feed RV power to safely utilize the RV alternator power to keep Toad alive.
There are probably some factors to be considered besides simply connecting a 12 V line from the RV engine battery source to the Toad battery.
What am I missing? Diode, fuse etc? I searched the forum but was not able to find anything.

All ideas are welcome.

carson FL
 

Gary RV_Wizard

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Get a marine grade battery disconnect switch - it will handle the load. If it corrodes within a year, you have a likely battery problem, e.g. excessive gassing is splattering sulfuric acid fumes around and corroding soft metals (the copper switch).

Example: Battery Disconnect

In its most simplistic form, you can simply jumper the house batteries to the coach batteries when traveling. Got to remember to disconnect the jumper when you stop for very long, though, cause you could drain the coach battery and not be able to start the engine the next morning. A cusomer made jumper with diodes would prevent that. Battery isolation units are designed for this purpose: JC WHitney Battery Isolator
 

carson

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Good morning, Gary
  Thanks for the reply. I have no problems with the House or engine battery situation.
I know what you mean re marine gear: I am old sailor too, ran a 25' Yamaha sailboat for years, then a 35' Chiw Hwa trawler for another bunch of years. Now i'm "boated out" and only want to use my Land "cruiser" if you know what I mean.

  My intentions were to only get a 12v feed to the toad, while towing it, without causing any feedback problems when hooked up and the starting the RV engine.
  My Jeep battery is virtually new and there is no sign of corrosion anywhere in sight otherwise.
  Only the bronze switch was affected, perhaps dissimilar metal interaction, etc.
I want to get away from disconnecting the Jeep battery while towing. The computer resets every time, which is probably not advantageous.

My thoughts were to run a medium wire from RV to toad, place a 5 or 10 a diode in the line to prevent toad battery drawdown when starting RV engine.This should keep the battery fully charged however long I tow it.
carson FL
 

Ron

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I guess I don't understand what causes the need to charge the battery in a Jeep while towing.  We have towed jeeps over 100k miles and never had the need to charge the Jeep battery while towing.  What year and model Jeep are you towing?
 

Ned

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If your battery is being discharged on a long day, then you have something turned on that shouldn't be.  You should be able to tow for at least one day without having to charge the toad battery.  Until you find the problem, stop every few hundred miles and run the toad engine for a few minutes to top off the battery.
 

Karl

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Carson,
Your idea is good, but remember that a diode will introduce a 0.6V drop in charging voltage to the toad battery. Also, It's not really necessary if you run a wire of sufficient size directly from a battery feed in the coach to the battery in the toad. I would suggest you install a lighted switch in easy view so you don't forget to turn it off when remaining hooked up for an extended period.
 

John From Detroit

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Well, first understand that you NEED brakes on the towed to be active when towing, The LAWS require it, In most cases the written law of the land requires it and in all cases the laws of Physics (Specifically Newton's laws) require it.  (Inertia v/s braking power)

Any wheel which is not bound by active brakes and which contacts the road will increase your stopping distance

That said: I choose a US Gear Unified Brake Decelerator

So, what does this have to do with the questin?

Since it uses electricity, the designers of the system wisely included a charge line for the towed, Hreavy guage (8ga) wire with a 40 amp breaker at each end
 

Ron

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John we have used the Brake Buddy for close to 150K miles and have NEVER had the need to charge that Toad batteries while towing.  Any well designed braking sytem should not require charging the toad batteries while towing.  In any case we have towed for several days without disconnecting the toad or even starting it and have not had a problem.

Now if the Jeep Carson is towing is a 2005 or later then the problem may be that they are leaving the ignition key in the on position.  On our 99 and 2001 GC the key had to be left in the on unlocked postion, one click back from the run position.  However, in 2005 the steering wheel lock feature was discontinued and the key moved from the steering wheel to the dash as well as the on unlock position was deleted.  On the GC 2005 on towing is done with the key in the off position with key removed.
 

carson

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This is in reply to Ron's last entry. I composed this message last hour and posted it, but alas, I can't find it now. Seems to have gone into cyberspace. I'll try to recollect what I was talking about now:

I have a 2000 Jeep Wrangler YJ, having towed it over 5000 miles by now.
In order to unlock the wheels I have to turn the ign. key to the Acces. position, one click ccw.
  This also energizes the Blaupunkt radio (even though the vol. control switch on/off position is OFF. The current draw is significant and will discharge the toad battery in time.(I am talking about a 2-3 day haul). In addition the car computer's draw is small, but it all adds up. Who knows what else is powered up.
  Please note that I don't want to pull fuses all the time.
All I want to do is feed the toad battery with an Rv generated dc current to keep the battery alive while towing. The .6 V drop of the diode should be neglible, as I'll be happy to keep the battery up to 11.5 to 12V.

I understand the aux. brake situation, but that is another matter.

I ranted a bit more in my "lost" message, but this is the gist of it.

I suppose that is workable and relatively easy to do. With my 40 years of elect. tech experience I have confidence. Thought maybe someone had the proven experience.
Thanx for all the help.   

carson FL.
 

Ron

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Your most recent Jeeps up to but not including 2005 that have the ignition on the steering column have a off unlock position.  Starting from the start position the next is the run position then the next position is the off unlock position, then the off locked position and followed by the Access position.  Doesn't your Wrangler have the off unlock position mentioned above?  If not I can understand your desire to charge while towing.  Does you owners manual give instructions for recreational towing?  I guess it just surprised me that you needed to charge the Jeep Battery while towing since I have never heard of this problem when towing a Jeep before. 
 

carson

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Hey Ron,
  You may have a point there. I have always used the acces. position. Did not know that the off position also unlocks the front wheels. My manual says zilch about that, re towing.

So I must check that out and see if my model year has that feature. If so, we've got it made.

Learning is an ongoing thing, especially on this forum. Someday wisdom will click in.  :D

Will let you know after I check it out
Tnx Ron,  carson FL
 

carson

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Ron, my good man,
  As you can see it didn't take me long to confirm your brilliant idea. The position between ON and the key out position I will call the TOW position. It works. It never occured to me what that position was used for. Oh well, I am wiser now, thanks to you.

    I'll forget about patenting my wire idea, Shucks. Maybe someone elses fire was lit by that idea, who knows.

Wanna buy a corroded knife switch. I'll dig it out of the dumpster.  ;D

Cheers,  carson FL
 

Gary RV_Wizard

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Carson,
Glad the problem was easily solved.

Sorry I missed the mention of TOAD in the thread title and went off on a tangent. Did not realize you were talking about the toad (it's not mentioned in the body of the thread till later on).  That sort of mistake happens fairly often when part of the question is in the subject but not in the text.
 

dazzer

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I see you've fixed your problem.  Well done!!  However on another note we use a dashboard mounted solar charger that simply plugs into the cigarette lighter to keep out toadbattery topped up with no link between rv and toad.  They are cheap and give free power and extremely easy to fit.

Just a thought to keep your batteries fresh.

Dazzer
 

Bob Buchanan

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Ron said:
Any well designed braking sytem should not require charging the toad batteries while towing.

Not true, Ron. The US Gear system "is" well designed -- in that it uses the power assist in the toad brakes. That's why it also keeps the toad battery topped off. I have been using the USG system for about 9 years and have never had a problem with the toad battery.

BTW, where you aware that Monaco now pre wires all of their line of coaches with the US Gear system? Doubt they would if they felt it was not well designed.  ;)
 

carson

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Hello Ron,
    I am following in your footsteps re Brakebuddy. Ordered a basic unit this morning (on sale)
including the break-away system, the wireless alert system, free shipping and of course no sales tax (FL). The whole kit and kaboodle for 799.00

(PPL Houston,Tx). After I saw CW prices, I was convinced.

carson, FL
 
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