Supplying power to camper

[nu2this]

Hello all.
Have been lurking for a while and have found this site to be very informative. I am a newbie regarding electrical concepts so please be patient with my questions.

Having a 5th wheel trailer and not wishing to drill holes in the roof I am looking at a portable suitcase solar option.Currently the system consists of two 6 volt golf cart batteries in series, two 100 watt panels a 30 Amp charge controller and a 2000 watt inverter.

If I connect the solar setup to my two batteries via a 12ga extension cord to the shore power output on the camper to the 2000W inverter, will this in turn energize all the 12volt receptacles as well as the 110v outlets? If it does, I assume I will need to pull all non necessary fuses and breakers. Is this correct? The only appliances I need to use will be the entertainment center, radio,tv,dvd player and a hair dryer for my wife.

Thank you, any help would be appreciated.

[Ampster]

I followed you as far as the extension cord from the solar panels to the batteries. You lost me at the shore power outlet. The issue I see is you may need some form of charge controller between the solar panels and the batteries.

Charging the batteries should not affect how the other devices work. Presumably the shore power when connected will charge the batteries so you may wish to have some mechanism for choosing between one source or the other. I also presume that the shore power and the inverter energize the 110v outlets. If it were me, I would make a simple line diagram to illustrate how my existing devices are connected before I added anything new. I also find it useful to have an AC DC voltmeter to test the circuits and determine which ones are controlled by which switches breakers or fuses.

[PNW_Steve]

I have worked on a number of RV roofs and keeping the roof leak free is critical to the lifespan of the RV.

When I have installed anything on the roof of a "sticks and Staples" RV proper sealing and maintenance are key. I have a 30 year old fifth wheel that has not had a problem. Every year I get up on the roof in inspect and touch up the sealer on all of the points where there is a seam or penetration.

I have seen folks that have used 3M-5200 with apparent success. I am not ready to trust glue at 70mph or more if I were driving into a headwind. Driving 60mph into a 40mph headwind exposes my panels to a 100mph wind.

When I put panels on my fifth wheel, I positioned the panel so that the leading edge was over a steel roof member. Then I glued the brackets down with 5200. Then followed with tek screws through the brackets and finally a thorough sealing with self leveling RV roof sealer.

Just my $0.02

Please let us know how it comes out?

[PNW_Steve]

Clarification: I have seen folks use 3M-5200 as the only thing holding their panels in place.

[nu2this]

Ampster,
Thank you, I guess my post was rambling a little bit. When I referred to the shore power outlet I was addressing a receptacle on the outside wall of my camper . This receptacle can be connected to any 110v AC source by a power cord, extension cord, portable generator etc. This in turn powers all the AC appliances as well as an onboard AC/DC inverter powering all DC lights in my camper. My intention is to connect my batteries to a separate 2000W inverter, run an extension cord from the inverter to the shore power receptacle. I believe this set up duplicates being plugged into a 110v outside source. What is your opinion?

The final objective of all this is to be able to watch TV, run a DVD player and have a hair dryer for my wife without using a noisy generator that would annoy other near by campers. I would simply only use the breakers for the needed items and disconnect all the others.

Would this work?

[Mike90250]

Works until the hair dryer. a pair of 12V batteries, might be able to power a hair dryer for a minute, maybe 2, but then I expect the inverter to go into low voltage shutdown.

1200watts of blowdryer = 120amps @ 12V If this is a requirement, look at four 6V golf cart batteries wired in series for a 24V bank, which would only suck 60A out of a 200ah rated battery, That might last 5 min before shutdown.

[nu2this]

Thank you.
The batteries are two golf cart 235AH six volt batteries in series. Maybe the wife will have to forgo the hair dryer. I really only want to run the TV and DVD player.

[PNW_Steve]

Thank you.
The batteries are two golf cart 235AH six volt batteries in series. Maybe the wife will have to forgo the hair dryer. I really only want to run the TV and DVD player.

Good luck with that!

I tried to talk my wife out of the blow dryer and curling iron. After that conversation I went out and bought a generator......

The genny will power us through the morning use of high demand loads and get a head start on charging my batteries.

[Ampster]

Ampster,
Thank you, I guess my post was rambling a little bit. When I referred to the shore power outlet I was addressing a receptacle on the outside wall of my camper . This receptacle can be connected to any 110v AC source by a power cord, extension cord, portable generator etc. This in turn powers all the AC appliances as well as an onboard AC/DC inverter powering all DC lights in my camper. My intention is to connect my batteries to a separate 2000W inverter, run an extension cord from the inverter to the shore power receptacle. I believe this set up duplicates being plugged into a 110v outside source. What is your opinion?

No worries, I don't understand that you were talking about a new inverter. Is there one in your RV or is the other device a charger or converter that takes 110v AC and converts it to DC. I think your idea will work as long as you have enough sunshine. The benefit of portable panels is that you can put them where they will get the most sun.

The final objective of all this is to be able to watch TV, run a DVD player and have a hair dryer for my wife without using a noisy generator that would annoy other near by campers. I would simply only use the breakers for the needed items and disconnect all the others.

Would this work?

Yes it should work except as others have said, the hair dryer might be two much load. It all depends on how long she takes to dry her hair. Wife acceptance is important. It might mean she would want you to buy more solar panels.LOL

[ewarnerusa]

I think your 2x6V batteries are a good foundation and 200 watts of portable panels with your charge controller is a good starting point although it's a bit light for charging that much battery. But your implementation plan confuses me.

Your batteries should already be hooked up to your main power distribution panel and they supply all the 12V DC power. So when you're not plugged into shore power, all your 12V DC lights/furnace/exhaust fans/water pump/etc. should be working. If they're not, something isn't right. Maybe fuse issue or disconnect engaged or not wired correctly. This is a default installation scenario and how any camper should work.

When connected into shore power or a generator via a power cord plugged into the receptacle on the outside wall of your camper, you are supplying 120V AC to your main power distribution center. This then feeds all the 120V AC (household) outlets in the camper as well as the air conditioner. It also energizes your AC to DC converter which takes over from your batteries as supplying the 12V DC and also charges the 12V battery system (2x6V in series in your case).

Your solar panels and charge controller are a separate system from the 12V battery and 120V AC power systems I just described. They will be connected to your 12V battery system and supply them with charging current when deployed. While technically the solar harvest can fulfill small 12V loads on the system, for simplicity you can think of them as just a charging system for the 12V battery system.

Your inverter is a nice gadget for converting 12V DC to 120V AC; however, 2000 watts is way oversized for 2x6V batteries and you'll never be able to run it at max capacity. But that doesn't mean it won't work just fine for small 120V loads like a TV or laptop charger. But forget about a hair dryer or electric coffee maker or microwave. The inverter should be wired directly to the 12V battery system with sufficient gauge wires which are kept as short as possible. Now I think I see what you're getting at with your implementation question, you want to use the inverter to energize all of the campers 120V AC (household) outlets as if you were plugged into shore power. We do this by plugging the shore power cord into the 120V AC outlet on the inverter. The camper's power distribution center doesn't care what is supplying the 120V AC power input and will pass the battery 12V DC->inverter 12V DC to 120V AC->shore power cord to receptacle on the outside wall of your camper along just like when plugged into true shore power. So you need to be aware of what kind of 120V AC load you put on the system because you'll be limited by what the battery 12V DC/inverter can provide. The main concern with this scenario is your camper's 120V AC to 12V DC converter. When it is energized, it will try to take over as the 12V power source and battery charger which will cause a power draining loop in this situation. You need a way to unplug or disconnect the converter from the camper's power distribution center when you've got shore power plugged into the inverter. Some converters just use a standard wall plug in which you can just unplug in this situation. Our camper had the converter wired directly into the AC power panel, so we added another AC breaker and isolated the converter to that breaker. I then use the AC breaker as an on/off switch for the converter which I switch to off when we plug shore power into the inverter.

[nu2this]

I think your 2x6V batteries are a good foundation and 200 watts of portable panels with your charge controller is a good starting point although it's a bit light for charging that much battery. But your implementation plan confuses me.

Your batteries should already be hooked up to your main power distribution panel and they supply all the 12V DC power. So when you're not plugged into shore power, all your 12V DC lights/furnace/exhaust fans/water pump/etc. should be working. If they're not, something isn't right. Maybe fuse issue or disconnect engaged or not wired correctly. This is a default installation scenario and how any camper should work.

When connected into shore power or a generator via a power cord plugged into the receptacle on the outside wall of your camper, you are supplying 120V AC to your main power distribution center. This then feeds all the 120V AC (household) outlets in the camper as well as the air conditioner. It also energizes your AC to DC converter which takes over from your batteries as supplying the 12V DC and also charges the 12V battery system (2x6V in series in your case).

Your solar panels and charge controller are a separate system from the 12V battery and 120V AC power systems I just described. They will be connected to your 12V battery system and supply them with charging current when deployed. While technically the solar harvest can fulfill small 12V loads on the system, for simplicity you can think of them as just a charging system for the 12V battery system.

Your inverter is a nice gadget for converting 12V DC to 120V AC; however, 2000 watts is way oversized for 2x6V batteries and you'll never be able to run it at max capacity. But that doesn't mean it won't work just fine for small 120V loads like a TV or laptop charger. But forget about a hair dryer or electric coffee maker or microwave. The inverter should be wired directly to the 12V battery system with sufficient gauge wires which are kept as short as possible. Now I think I see what you're getting at with your implementation question, you want to use the inverter to energize all of the campers 120V AC (household) outlets as if you were plugged into shore power. We do this by plugging the shore power cord into the 120V AC outlet on the inverter. The camper's power distribution center doesn't care what is supplying the 120V AC power input and will pass the battery 12V DC->inverter 12V DC to 120V AC->shore power cord to receptacle on the outside wall of your camper along just like when plugged into true shore power. So you need to be aware of what kind of 120V AC load you put on the system because you'll be limited by what the battery 12V DC/inverter can provide. The main concern with this scenario is your camper's 120V AC to 12V DC converter. When it is energized, it will try to take over as the 12V power source and battery charger which will cause a power draining loop in this situation. You need a way to unplug or disconnect the converter from the camper's power distribution center when you've got shore power plugged into the inverter. Some converters just use a standard wall plug in which you can just unplug in this situation. Our camper had the converter wired directly into the AC power panel, so we added another AC breaker and isolated the converter to that breaker. I then use the AC breaker as an on/off switch for the converter which I switch to off when we plug shore power into the inverter.

ewarnerusa,

You NAILED IT!!!!!!!!
That's exactly what I want to do and you understand the situation perfectly. In my RV camper I have two 12volt interstate batteries that as you know power all the DC needs but they do not have the amperage of my 2 6volt 235AH Crown golf cart batteries. I was hoping to use the 6 volts in series to allow my wife to use the hair dryer and then recharge them the next day with my solar panels. This would be a separate battery bank. The reason I need to have it separate is I don't want to mix and match dissimilar batteries. I now realize my wife might not be able to use the hair dryer.-----------------Uh Oh!

I believe I am going to have to disconnect my onboard inverter whilst using my battery/separate inverter however. The inverter is connected to the batteries via 2AWG gauge wire 3' in length with an 100AH ANL fuse between the two on the positive lead. I don't know if my converter is wired into the AC power panel. I'm hoping for a simple solution.

Thanks again for your lengthy and informative post. This should be a primer for anyone contemplating doing what I am trying to do.

[ewarnerusa]

You're welcome! Good plan on not mixing batteries, but I also see a potential to put a 4-battery system together. Matched batteries, of course. Now you're getting into the territory where you can fully exercise that big inverter and run that hair dryer. But also getting into a danger zone with the amount of DC amps the inverter could pull so you'd need to address that. 2000 watts / 12 volts = 167 amps. Your current solar would also be insufficient for recharging all that battery.