Solar Panel Trickle Charger?

Robert Engleheart

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I want to be able to maintain the RV batteries (2 x 6 volt golf cart) while it’s parked where there’s no shore power. Getting tired of disconnecting the batteries and hauling them into garage while the trailer is parked in my backyard where there’s no power. trailer has a Charge Wizard by Intelli-Power that will modulate the rate of charge to prevent over charge and sulfation. Automatically goes into trickle mode when no power use is detected.
I think a 60watt panel would be more than sufficient, not sure if they come much smaller than that. Anyone doing this?
 

Eastside

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I have two 12 volt batteries on my trailer set up by the dealer. Was planning on having a 90 watt panel installed by the dealer, but a couple of co-workers gave me a folding 100 watt panel when I retired. It recharges the batteries in less than an hour, but the new batteries never drop very far from full charge. I imagine that a 60 watt panel would work fine, but perhaps others will weigh in.
 

Old406Kid

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I want to be able to maintain the RV batteries (2 x 6 volt golf cart) while it’s parked where there’s no shore power. Getting tired of disconnecting the batteries and hauling them into garage while the trailer is parked in my backyard where there’s no power. trailer has a Charge Wizard by Intelli-Power that will modulate the rate of charge to prevent over charge and sulfation. Automatically goes into trickle mode when no power use is detected.
I think a 60watt panel would be more than sufficient, not sure if they come much smaller than that. Anyone doing this?
I have two 12vdc batteries wired in parallel for my backup generator at my off grid cabin and use a solar maintainer.
It always starts when needed.:)
I just reread your post, are you talking about maintaining the batteries when your RV is not in use or while using power?
 
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Robert Engleheart

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I have two 12vdc batteries wired in parallel for my backup generator at my off grid cabin and use a solar maintainer.
It always starts when needed.:)
I just reread your post, are you talking about maintaining the batteries when your RV is not in use or while using power?
The latter. I want to maintain the charge when not in use. What brand of solar maintainer are you using?
 

Robert Engleheart

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I have two 12 volt batteries on my trailer set up by the dealer. Was planning on having a 90 watt panel installed by the dealer, but a couple of co-workers gave me a folding 100 watt panel when I retired. It recharges the batteries in less than an hour, but the new batteries never drop very far from full charge. I imagine that a 60 watt panel would work fine, but perhaps others will weigh in.
Do you charge the batteries directly, at the batteries using 12v, or through the 120vac shore power connection?
I would want to go through the 120 vac as that will enable the Inteli-Wizard to act as a float charger and keep the batteries from overcharging and sulfation.
I believe my logic is correct, let me know if I’m overthinking it.
 

Old406Kid

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The latter. I want to maintain the charge when not in use. What brand of solar maintainer are you using?
Mine is really old and at my place in MT so I can't look.
I think it's only 20 watts, or possibly even less, but it does the job. I just have it mounted on my south facing garage wall.
If you shop for one look for units with a MPPT charge controller as they're more efficient than those with a PWM controller.
That said, mine is so old that I'm sure it's a PWM model and it goes straight to the batteries.:)
 

Old406Kid

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Do you charge the batteries directly, at the batteries using 12v, or through the 120vac shore power connection?
I would want to go through the 120 vac as that will enable the Inteli-Wizard to act as a float charger and keep the batteries from overcharging and sulfation.
I believe my logic is correct, let me know if I’m overthinking it.
I'm not familiar with the Inteli-Wizard but solar panels only produce dc power unless the Wizard has some sort of inverter.
 

Robert Engleheart

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I'm not familiar with the Inteli-Wizard but solar panels only produce dc power unless the Wizard has some sort of inverter.
The Wizard is basically a smart maintainer that automatically sends the correct charge to the batteries, has several modes and you can override any of them.
Will do some research on this, not sure the cheap ($50/20W) chargers have a reliable controller similar to what you describe.
 

Old406Kid

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not sure the cheap ($50/20W) chargers have a reliable controller similar to what you describe.
Probably not but the unit you're looking at appears to have to tie to the converter in your RV if it's compatible.
Basically it has the same functions as most decent dc charge controllers.

Some info that may help in your decision.
 

Chris M

Steelhead
I believe that your charge wizard controls the 12 volts coming out of your converter when plugged into shore power. A solar charge/maintainer system would be independent of the converter. Basically you would have a solar panel to solar charge controller to battery. The solar charge controller will charge in 1 of 4 modes automatically depending on battery state of charge. The newer MPPT controllers are more efficient than the PWM controllers but cost more. If you are just maintaining or charging over a long period of time ( days) the PWM would be fine. I dry camp alot, 49 day last year, and do well with my solar system but it would be larger than what you might need. I have used products from RENOGY for the last 6 years with no problems at all and would highly recommend them. Renogy currently has a kit on sale for $102.00 free shipping. 50 watt panel, charge controller, cables. A 50 watt panel is very sufficient for maintaining batteries.
 

_WW_

Geriatric Skagit Swinger
Forum Supporter
Never hook a solar panel to a battery without a charge controller. I have a little 60 watt suitcase panel that came with a controller. If you just want a trickle charge you can go smaller. But the 60 watt will be more useful because it will help when you are boondocking.
 

Robert Engleheart

Life of the Party
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I believe that your charge wizard controls the 12 volts coming out of your converter when plugged into shore power. A solar charge/maintainer system would be independent of the converter. Basically you would have a solar panel to solar charge controller to battery. The solar charge controller will charge in 1 of 4 modes automatically depending on battery state of charge. The newer MPPT controllers are more efficient than the PWM controllers but cost more. If you are just maintaining or charging over a long period of time ( days) the PWM would be fine. I dry camp alot, 49 day last year, and do well with my solar system but it would be larger than what you might need. I have used products from RENOGY for the last 6 years with no problems at all and would highly recommend them. Renogy currently has a kit on sale for $102.00 free shipping. 50 watt panel, charge controller, cables. A 50 watt panel is very sufficient for maintaining batteries.
Thanks ChrisM,
that will work. I have a situation where I will park the Fox on a riverfront space with full hookups while I’m there and when I’m not, rather than haul it 400 miles home, I can move it 200’ to a space with no connections. It might stay there for a week or a month or more, which is where I want to use the solar panels/maintainer.
 

Robert Engleheart

Life of the Party
Forum Supporter
Never hook a solar panel to a battery without a charge controller. I have a little 60 watt suitcase panel that came with a controller. If you just want a trickle charge you can go smaller. But the 60 watt will be more useful because it will help when you are boondocking.
Thanks Wayne,
That 50W panel with maintainer that Chris M talked about sounds perfect. When boondocking I have a 3.5 kW generator that’s built in and runs on propane if I need to charge the batteries. Kinda loud, so I don’t use it unless I really need to. Changed all the lights to LED a couple years ago.
 

_WW_

Geriatric Skagit Swinger
Forum Supporter
One of the best things you can do is put a on/off switch on your batteries. That way you can disconnect them by simply turning a switch. I mounted mine right on the outside of the battery box. Then just throw 'em a charge every month or so.
 

Pescaphile

Steelhead
I use a Victron Energy solar charge controller and a 100 watt panel to maintain two 12volt battery banks of 2 6V golf car batteries in series (four batteries). It cycles the batteries through bulk and absorption charging phases then floats the batteries at 13.5 volts. Absorption energy is varied depending on battery usage and if just maintaining a battery will only keep batteries at absorption voltage (14.8 v in my case) a short time. If you've been discharging the batteries it will keep it there longer. You have many options to select for charging profiles depending on battery type, e.g. ;ead acid, gel, Li, etc.

You can get a Victron 75/10 which is suitable for your application for $80. Or get one with bluetooth so you can easily monitor the batteries for $109. I use a bluetooth model and the solar system has been one of the best things I've done for my boat. Batteries are always "hot" and will last longer than when used in a partial state of charge. I highly recommend Victron Energy equipment, it's all first class.

 

Dblhaul

Just Hatched
I have a 100W Renogy system for my RV, running two 6V golf cart batteries. I will run down the charge a bit in the evening running lights and heater. It will be fully charged by noon the next day.
 
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