I'd be curious what size wire runs to your parent's camper. From what DiploStrat is saying, perhaps the issue is undersized wire. But you've sold me on solar. And I appreciate the education both of your are giving me. Thanks!
Battery Charging Techniques and Safety
- Thread starter Stereo
- Start date
I'd be curious what size wire runs to your parent's camper. From what DiploStrat is saying, perhaps the issue is undersized wire. But you've sold me on solar. And I appreciate the education both of your are giving me. Thanks!
tanglefoot
ExPoseur
Their camper has some pretty hefty wire--I think it's about 10GA. It's a commercially-built, one-piece, micro-mini class-C RV...the battery wiring was done at the factory and uses an isolator, which I've read doesn't do as good of charging as a solenoid.
I really like the camper having a self-standing solar-electrical system. Have you been to the Colorado Mountain Club cabin near Brainard Lake? I like how it has off-grid power from a panel, charge controller and a few batteries. With the camper, it's fun to have my own "solar cabin". While it's parked, it's a little free-power station. I like to take gadgets and batteries out to the camper to charge them so that they're solar-powered too.
I really like the camper having a self-standing solar-electrical system. Have you been to the Colorado Mountain Club cabin near Brainard Lake? I like how it has off-grid power from a panel, charge controller and a few batteries. With the camper, it's fun to have my own "solar cabin". While it's parked, it's a little free-power station. I like to take gadgets and batteries out to the camper to charge them so that they're solar-powered too.
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DiploStrat
Expedition Leader
When it comes to camper batteries, 10GA is tiny. Depending on the length and the load, the good stuff starts at 4GA and can go into the double aught range. An isolator almost always introduces a .75v drop or more. Once your charge voltage drops below say 13.5v you can drive all day and you will never charge the battery.
Batteries need two things to charge:
-- Enough current, amperes, to replace 110% of the discharge, and,
-- Enough voltage, say over 14v, to overcome the resistance of the battery. (Think of the difference you trying to blow up a ballon and a truck tire with your breath. You can produce enough air (current/amperes), at least eventually, but you can probably never blow hard enough to actually get the air inside the tire.)
Thus the raison d'être for battery to battery chargers.
SoCal Tom
Explorer
My experience with multiple dual battery systems is that none of the dual battery systems was reliable when I used them. What worked for me was a combination of a solenoid and a marine battery switch. Solenoids will stick on occasion, which means both batteries are connected, which always results in the two batteries discharging each other. With the marine switch I can select either battery, or both for charging, and I hooked up the house battery through a solenoid. When driving I selected both batteries, once parked I disconnected the main battery with the switch and then no worries.
Tom
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Tom
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BigWapiti
Mike
Could anyone recommend a good, brain-free, smart chargers? Trying to understand proper battery maintenance is hurting my head - I guess I just need something I can plug in and let the unit do the thinking. I'd like to use it to charge my RV/Marine batteries that are in my boat and camper through the year - so I'm hoping to find something that is portable, easy to move from toy to toy. Although I'd love a $400 unit - I just can't afford it. Are there any good models for around $100?? Or what might you recommend? Thanks in advance - I'm a new guy to the forum.
jbob
Observer
Not sure if you've seen this thread, but there's a ton of good info in there.
I just installed a Samlex SEC-1230UL in my rig based on a recommendation (for the smaller SEC-1215UL) in that thread. Unfortunately, it's permanently mounted, which isn't what you're looking for. I'd take a look at the Noco genius g7200 -- it does what you need it to do and is within your price range.
HTH
>>>---WW---->
New member
I always thought your battery charged back up when driving down the road through your camper inverter.
Another way might be to run a 1000 watt inverter off your truck battery and plug a small battery charger into it. Or, the charger supplied by a portable generator hooked directly to your battery.
Someone please correct me if I'm wrong!
Another way might be to run a 1000 watt inverter off your truck battery and plug a small battery charger into it. Or, the charger supplied by a portable generator hooked directly to your battery.
Someone please correct me if I'm wrong!
DiploStrat
Expedition Leader
The short answers are:
-- It depends. But if you have common RV wiring, it is very unlikely that you will ever charge a second battery.
-- There is no short answer as there are too many variables.
To design a decent system you must know:
-- Battery current and voltage requirements. For a typical AGM that comes out to C1 or better @ 14.4v @ 20C. Change any of these, and it all changes a bit. So a 200 Ah battery bank, which would give you 100 Ah usable, might like like to see as much as 200A @ 14.4 for about an hour @ 20C, followed by two to four hours of 14.4v at dropping current.
-- Knowing that, you can select and size your charge sources - alternator, solar, shore power.
-- Typically you are going to be looking at cables of 1/0 or larger.
The bigger your battery bank and the further it is from your charge source(s), the larger everything is going to be.
Dig around on this site for a while. http://www.smartgauge.co.uk/technical1.html
Warning:
-- A LOT of reading here.
-- While everyone will agree with his description of the problem, some prefer other approaches.
Good luck!
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