Recharging batteries

[IanC]

Having gone a through a few days of cloudy, rainy weather, my trailer batteries have dropped too low to run the fridge or inverter. I have them re-charging from my truck at the moment on jumper cables.  Is there any downside to that? Any possibility of damage to the solar controller, etc?

 

[IanC]

Damn, I don't know what just happened there, but my jumper cables just melted. I have done this before a couple of months ago and that never happened. That was close - I'm glad I noticed it - almost had a big time fire in here.

 

[abnorm]

Can you visit an auto parts store and get a battery-check-quickie-recharge ?

 

[IanC]

Can you visit an auto parts store and get a battery-check-quickie-recharge ?

I'm pretty far out in the boonies - I don't want to move the trailer until the ground dries a bit. This place has some nice grass and don't want to damage it. Looks like I'll have to live a little primitive for a couple of days and hope the sun comes out for a while to get some charge.

 

[ArtW]

holy crap, glad you caught the melting cables, i wish i knew what to advise here

 

[highdesertranger]

the cables should not have melted. my first guess would be severely depleted batteries and cheap cables passing to many amps. while not the most efficient way to charge your batteries it should work without a hitch. I have done it more than a few times. you will not hurt your solar controller. highdesertranger

 

[John61CT]

DCDC charger, at the low end Optimate tm-500 (slow) or CTEK Dual 250s (faster, better quality)

Going direct batt2batt from full to a larger empty one, vehicle probably saved by target bank's low CAR, FLA or AGM? How many AH?

if that were LFP likely boom like a short across the terminals.

 

[Optimistic Paranoid]

For future reference, there are places that will build you jumper cables out of heavy welding cables.  Not cheap, but stuff like that is a lifetime investment.

 

[IanC]

Yes, these were cheap cables I got at Walmart just because of their length. I have some heavy duty ones too. If I can position the truck to reach, I'll give it a shot later.

 

[SternWake]

Lots of cheapo jumper cables have 10 or 12awg copper clad aluminum wire, with really thick wire insulation to make them appear as if they are real jumper cables.


These questions are for my curiosity.
How much trailer battery do you have?
Can you see the melted jumper cable wire thickness at the alligator clamp? guess at the wire gauge?  Where did the insulation melt?


Your tow vehicle's alternator might overheat with thicker jumper cables attached to those depleted batteries.  Do you have a way of measuring its temperature?  220F is the max 'safe' limit, and can be acheived in about 10 to 15 minutes, perhaps less, when maxing out an alternator without moving the vehicle.  It really depends on vehicle platform.

Underhood airflow and higher alternator rpms when driving spin cooler air through the alternator, faster, making driving more effective than idling, and easier on alternator.  Higher Idling rpms will move alternator fan faster, but perhaps not move underhood air any faster.

 

[Dennis]

Good you caught that before it got worse. Might get some sun this evening...might. If you get in a bind with your truck battery or get stranded there send me a PM and message here. I'm close enough to give you a hand.
Got a lot of rain and lightning here last night. Been without power for the most part since about 8:00 pm. Still out.

 

[IanC]

I'm almost too embarrassed to post this. Another example of my incompetence. In connecting the clamps to the trailer batteries I attached the negative to the wrong post. Damn, I'm a friggin idiot. Thank God the cables melted and I smelled the burning plastic before my batteries blew up or something. Anyway, those cables are history but I used my heavy cables and now have enough charge to run my stuff.

Makes me wish you could delete your posts. I'd delete this one and pretend it never happened.

 

[SternWake]

**** happens. Yesterday I watched myself clamp a black cable clamp onto a terminal that already had a red clamp on it.

Luckily there was nothing connected to the powerpole connector at the other end, but red to red, black to black, would seem to be so easy to not F up. Perhaps my self destructive subconscious has an affinity for seeing sparks.

 

[Dennis]

We all do things backwards sometimes. At least you didn't need the fire dept so all is well.

 

[user 37446]

+1 to all advice above. You'll need the much thicker battery cables for emergency. I also think that you should get to a place to get recharged instead of waiting for proper solar conditions, as that might take a week and you may not have that time.
Do you have an alternator to continuous duty solenoid to batteries system? That's not too expensive (I'd say under $200 for everything, even under $100 if you can scrounge the wiring). Just make sure to fuze it, for obvious reasons...

Oh, I just read that you crosswired. Well, hopefully you paid for that lesson only with the cheapo WM cables. (What lesson, I never saw that post...)

You could ask the mods to delete your account, wiping all traces of the goof up off the forum.  Then come back with a new snazzy user name and talk about watching some guy nearby almost burn down his vehicle by crosswiring.