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Old 04-19-2010, 01:30 PM   #1
Join Date: Mar 2009
Posts: 40
SUN #811
Battery Charger

A question on the output of the on-board battery charger in my 1996 T2670 Solaris. Does anyone know the Amperage output from these trickle chargers?

Second question, if the answer to my first question is 2-3 amps, what would I have to do to use an external 10amp charger? Disconnect the battery from the RV leads?

I'm asking because I'll be camping with no shore power at all and that's for the entire summer. We have a Genset from which I can pull 120V directly and run a portable battery charge if needed. Since I do not want to run the Genset for more than a 3-4 hours per day I am concerned about the ability of the on-board charger to restore the battery charge each day. The 10 amp charger would probably do the trick in a couple of hours but having to constantly decouple the battery does strike me as a major pain.

One note on daily battery usage, it will be very very light, probably an outside light for a couple of hours, 2-3 inside lights for an hour perhaps, might run the radio if it rains and we're stuck inside.

The battery is a new group 24 AGM.

Thanks for any advice you might have.


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Old 04-19-2010, 09:38 PM   #2
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Hi Al

Can you supply us with a brand and model of your converter? We can then talk better on this.

Not knowing what you have, these converters are not trickle chargers. If yours is original and being a 96 unit, it may only have a normal charge, 13.65 volts and ďmaybeĒ a float charge, 13.25 volts.

From what I know of the mid 90ís units many seemed to be 30 amp converters. They would create a 30 amp DC supply to run lights, water pump etc and give a level of battery charging. And if you had on 30 amps of power in the camper, not that hard to do pending what all you have one at once, then there was nothing left to charge with.

Most of these converters ( the newer ones at least) are sort of setup to only charge the battery at about a max rate of 80% of itís 20 hour capacity rating. And in your case that might be 8 to 12 amps max. They do that I do believe to help control the heat the battery takes on from multiple charges. Pumping large high current dumps into a battery constantly has been know to shorten itís usable life so they on purpose take it slower in the deep cycle systems at least from what I have read in my search to learn about this.

Now you mentioned trying to keep the battery up with a genny on only 3 to 4 hours a day. That can be tricky even on a very high end new 3 stage charger. Charging batteries to full 100% takes a long time. Even a high end charger that goes into bulk 14.4 volts mode dumping a whopping 12 to 15 amps into a group 24 battery can take many hours to get it to even 90% charged. How long to that 90% charged number depends on how drawn down it is. If you only go to the 50% range as good practice pending usage that could take 4 to 5 hours to 90% and then 12 hours or more at 13.65 volts to get to 100%.

Standard RV light bulbs suck power big time. Us that boondock on batteries and a genny have gone into light bulb power miser mode. I myself have 5 LED lights placed in just the right spots as they only draw 0.25 amps for the same light output as a 1.0 to 1.2 amp normal bulb.

If you are going to live in the camper for months on end and never hook to shore power, a solar charge, a total power review to trim excess wasted amps and a new day 3 stage charger/convertor on the genny may be more what you need. And 1 battery may not cut it. I have 2, group 27ís and I have to keep on top of them. Your AGM is better then my lead acid battery but still I have more amp hours available.

Iím not saying it is impossible to get by on 1 group 24, but you will need to count up amps used and make sure do not drain below 50% state of charge and then bring it back up.

Hope this helps


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Old 04-20-2010, 07:43 AM   #3
Join Date: Mar 2009
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SUN #811
John, my converter is the Magnetek 6336. Looked but could not find specs on it. However it does sound like the on-board charge will be just as effective (or ineffective) as a portable 10 amp charger.

As for actual usage of the battery, this is not a situation where we are in the trailer full-time, It's a campground situation and I visit 6-7 times a year (it's a 320 mile trip to get there). We use it as a fishing camp and 90% of the time is spent outdoors. I'm very careful with the lights used, in the evening there is one outdoor light on and then some reading lights for a bit at night. Might run the radio if we can get a clean signal. Since we're used to very limited power (when we had campground power it was for just 7 hours a day) we tend to be very careful about taxing the battery. However that 7 hours per day was always enough to keep the one battery working just fine.

My plan for the Genset is to try to run it as little as possible yet keep the battery near full charge. I was hoping that 4-5 hours a day would be sufficient. We'll have to try it and see. The crucial thing is to maintain enough charge to get the Genset running. I need about 350-400 amps to do that.

I will take your advice and look for some LED lighting.

Thanks much.
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Old 06-03-2015, 04:46 PM   #4
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I too have a converter problem with my 2002 Solaris. Last season noticed my 12v bAttery was not holding a charge on 110ac power. Purchased new battery. Now no 12v lights/appliances work and no charging of battery occurs on ac power. All fuses and circuit breakers look good. Camper is stationary and wiring looks good. I do have power to trailer power tongue and light, nothing else works except in 110ac. If I need a new converter how hard are they to change over. Don't like messing with anything I can't see.
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Old 06-03-2015, 07:12 PM   #5
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krazedave is an unknown quantity at this point
The first thing I would do is double check your 30 amp fuses in your converter all 12 volt and your battery charge are through them. Even if they look good try new ones. Your tongue jack works because it is hooked directly to your battery and does not go through converter.
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Old 06-04-2015, 02:18 PM   #6
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Thank you I will try that.
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Old 06-05-2015, 08:07 AM   #7
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mainah is an unknown quantity at this point
It's a 36 amp unit but there were two different types and that effects the charge rate either way you still should be able to charger your battery depending on how discharged you get it. Power reduction is the key I replaced my lighting the incandescent bulbs drew a whapping 27 amps I replaced and added 2 more LED lights the power draw dropped to 3.08 amps! I charge my batteries (two group 24’s) with a 100 watt solar panel and can go all most indefinitely with that set up so your charger should be able to keep up.

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