Portable Solar Panels

[Mr Geek]

Hello everyone. Well I finally broke down and purchased solar power for my 2005 2619. I bought two 80w portable solar panel kits as shown here: http://rvsolarnow.com/80-watt-portable-RV-and-marine-solar-power-charger-maintainer-SLP80F-12.htm

A very nice feature is when folded and packed in the included padded storage bag, both panel kits fit under the dinette seat with room to spare.

You can use up to 4 of these portable kits totaling 320 watts. With two panels I will have 160watts. My hope is to have enough power to run a nice laptop computer I use for everything from HDTV, internet, emailing and gaming that uses 130 watts, leaving 30 watts for misc low power items like LED lighting, toilet and water pump. I won’t be using the laptop all day BUT I assumed I would in my power needs.

I am not sure how the furnace will impact this, but I know it will be very significant. I have a feeling without the furnace in the mix these panels will work pretty well, but with the furnace running I am not sure I will see my voltages remain healthy. Real world testing is needed.

I got the portable type solar panels because I travel with pets and park in the shade when possible, so having the flexibility to move them around will be nice...they will be cable locked to my RV to prevent them from being stolen.

I am going to camp in my backyard to see just what is realistically doable with 160 Watts of solar power feeding my dual 6v golf cart batteries, whether it will keep the battery voltages from dropping day after day or not. I have never used solar power before so I welcome any input on the matter. I know many here have installed panels, I remember seeing Wayne’s rooftop installation that was removable while towing, a great job and idea.

Mainly I am curious whether I will need to upgrade the converter or any other issues that others have worked with that may help me obtain the best results from these new panels.

Also the dealer sent me a very helpful RV appliance and utility power usage guide that helped me figure out how many panels I needed (see attached).

I will post back how well my backyard camping tests go.

[rumbleweed]

Be interested in the results of your backyard experiment. When you figure in efficiency and losses in the line from solar panel to batteries and in the controller, I am guessing you will have about 100-120 wattsmax. Per their spec, 4.65 amps at 14V ( charging mode) is about 65 watts per panel at full efficiency .

[Mr Geek]

Be interested in the results of your backyard experiment. When you figure in efficiency and losses in the line from solar panel to batteries and in the controller, I am guessing you will have about 100-120 wattsmax. Per their spec, 4.65 amps at 14V ( charging mode) is about 65 watts per panel at full efficiency .

Unless I am calculating this wrong the panels are 17.2 volts at 4.65 amps which calcs to 79.98 watts. I don't know about efficiency and what the real world results will be. It will be very interesting. I will definitely post back on what I found. I also am installing a Cobra 1500W inverter under the dinette seat on the forward bulkhead. When finished I am hoping to end up with an "ok" solar solution for dry camping as well as providing power when the big one hits :eek:. I live in So Cal and that is always a possibility. It's nice having the TM available with 40 gals of fresh water if such a scenario becomes reality.

[rumbleweed]

You are correct, the panels generate 17.2V @4.65a, but what comes out of the charge controller is about 14V at max of 4.65a. ( 17.2V would damage the battery).A good way to check is to actually measure the current out of the charge controller under heavy load. Also keep in mind when connecting your inverter, you will need very heavy short cabling as it will require about 130+ amps from the battery if you ever use all 1500 watts.

[Bill]

Bob is right. The numbers associated with solar panels are a bit tricky to work with. If a panel is putting out 4.65 amps, then 4.65 amps is what will come out of the controller and into the battery. The purpose of the controller is simply to reduce the voltage to whatever the battery can accept. Sadly, the extra voltage is simply wasted.

However, there is way to beat this. The behavior Bob and I described applies to a simple PWM controller (which is what you and I both have). There is a magic controller called an MPPT controller that will convert the excess voltage to more current. It is considerably more expensive, and at the power levels being discussed, probably isn't worth the added cost. But we have had discussions of MPPT controllers on this board - you can look them up with the Search tool.

Your post describes consuming almost all of the 160 watts of solar power as soon as it is generated - laptop, etc. Realistically, the small amount of power that is left over - and then, only under optimum sun - won't do anything to recharge your battery from any discharge that it undergoes. You are right, the solar power will substitute for power that would otherwise come from the battery, and so the battery will last longer. But you are right again in saying that the furnace blower, as well as lights and other loads, will still come out of the battery. So don't expect magic results here.

Way back in the very early days of the Solar Power forum, Rocky Mountain Ray did a real nice installation. He dry-camped high in the Rockies (perfect sun every day!) on a regular basis, and he was an electronic gadget guy as you are. He installed, as I recall, about 300 watts of power, which allowed him to do what he wanted. You might consider digging up his story.

The owners of Northern Arizona Wind and Sun are technical guys, and their web site has a real nice technical section that is devoid of advertising hype or product-pushing. It is also technically accurate and honest, without the "wisdom" that comes from somebody's brother-in-law's cousin. It is located at www.windsun.com. Their goal is to make a smarter customer. I have learned more from this site than from anything else on the web.

They also have a store, separate from the tech site. It is located at store.solar-electric.com. (They also have a walk-in retail store.) I recommend them, having owned a bit of stuff from them. Their prices are quite a bit lower than other sources. Not to be a wet blanket, but you could have built the same system for about $350 less.

Meantime, welcome to the solar family. Since there aren't many of us, we will all be watching for your experiences and reports.

Bill

[Mr Geek]

You are correct, the panels generate 17.2V @4.65a, but what comes out of the charge controller is about 14V at max of 4.65a. ( 17.2V would damage the battery).A good way to check is to actually measure the current out of the charge controller under heavy load. Also keep in mind when connecting your inverter, you will need very heavy short cabling as it will require about 130+ amps from the battery if you ever use all 1500 watts.

Thanks for the information. For wiring, I ordered the installation cabling they sell for this unit which uses 4 GA cabling. The lengths will be the shortest possible without mounting the inverter outside, which would only gain me 6" or so, being just on the otherside of the wall I will be mouting to. It will be located inside the RV under the curb side dinette seat mounted on the front bulkhead. I plan on adding some open framing around the inverter to make sure a clear air area is maintained to provide ample space for proper venting/cooling. If heat ends up being a problem I may mount it outside.

For battery monitoring I ordered the newer Clipper battery monitor shown here in the link below. After reading through the forum it sounds like this is an acceptable monitor that provides crucial information necessary to get the most out of this system:
http://www.amazon.com/gp/product/B003UY7ERK/ref=oss_product

Hopefully when this project is complete I will have a solar system in place that works well enough to allow fairly long, power conserving camping trips without too much pain and sacrifice.

[Mr Geek]

Bob is right. The numbers associated with solar panels are a bit tricky to work with. If a panel is putting out 4.65 amps, then 4.65 amps is what will come out of the controller and into the battery. The purpose of the controller is simply to reduce the voltage to whatever the battery can accept. Sadly, the extra voltage is simply wasted.

However, there is way to beat this. The behavior Bob and I described applies to a simple PWM controller (which is what you and I both have). There is a magic controller called MPPT that will convert the excess voltage to more current. It is considerably more expensive, and at the power levels being discussed, probably isn't worth the added cost. But we have had discsussions of MPPT controllers on this board - you can look them up with the Search tool.

Your post describes consuming almost all of the 160 watts of solar power as soon as it is generated - laptop, etc. Realistically, the small amount of power that is left over - and then, only under optimum sun - won't do anything to recharge your battery from any discharge that it undergoes. You are right, the solar power will substitute for power that would otherwise come from the battery, and so the battery will last longer. But you are right again in saying that the furnace blower, as well as lights and other loads, will still come out of the battery. So don't expect magic results here.

Way back in the very early days of the Solar Power forum, Rocky Mountain Ray did a real nice installation. He dry-camped high in the Rockies (perfect sun every day!) on a regular basis, and he was an electronic gadget guy as you are. He installed, as I recall, about 300 watts of power, which allowed him to do what he wanted. You might consider digging up his story.

The owners of Northern Arizona Wind and Sun are technical guys, and their web site has a real nice technical section that is devoid of advertising hype or product-pushing. It is also technically accurate and honest, without the "wisdom" that comes from somebody's brother-in-law's cousin. It is located at www.windsun.com. Their goal is to make a smarter customer. I have learned more from this site than from anything else on the web.

They also have a store, separate from the tech site. It is located at store.solar-electric.com. (They also have a walk0in retail store.) I recommend them, having owned a bit of stuff from them. Their prices are quite a bit lower than other sources. Not to be a wet blanket, but you could have built the same system for about $350 less.

Meantime, welcome to the solar family. Since there aren't many of us, we will all be watching for your experiences and reports.

Bill

Hi Bill, thanks for some great insight and the howdy, there are tons of great people on this site, it's a joy to plop down at my PC and spend quality time enjoying all things RVing and TM.

On expense, yes I realized upfront the option I chose was NOT the cheapest, not even close. I have read through the solar threads, saw the excellent job Wayne did with his two panels that have the same power mine do for about 1/3 the cost of what I am doing.

I really like the portable aspect of the panels I ordered and the ability to simply add more kits to get from 80w to 320w setup. I realize this isn't rocket science to do that with any solar setup, but it's just a bit easier with these turnkey kits.

The CEA Solar rep has been extremely helpful and I found he's well known in RV solar solutions. He even answered his phone at 7:30 PM on Saturday and was courteous and kind in taking whatever time it took to answer my questions. I was pleasantly surprised.

On the actual electron dynamics that occur once the solar panels are connected and supplying power is a bit of a mystery to me and I haven't asked about this yet, so I will now. Obviously I have lots to learn.

I wondered with these PWM type controllers, how is power allocated when the panels are active. Initially the main question that I have relates to what I believe you touched on in your previous post.

Assuming the panels are in full sun and connected, with a load being applied inside the RV that is LESS than the output capacity of the panels:

1 - Can the system both charge the batteries AND provide power as pass-through energy to devices/appliances?

2 - Does the power that's output out of the controller ONLY come from the batteries? (IE - It never can be directly output from the solar panels to any device OTHER than the batteries.)

Ok then if question 1 = NO and 2 = YES then it seems a simple analogy could be that my batteries are a water tank. The solar panels are like a hose flowing IN to the tank. My appliances are like a drain flowing OUT of the tank. IF I have more water coming IN throughout the daytime (active power state for panels) will my batteries remain and be fully charged at the end of that daytime period? Is it that simple?

I imagine it's much more complicated than this but this might get me on the right track for now.

Thanks!
Bob.

[Wavery]

We've had a 160W system on our TM for 14 camp-outs now (most were 4 days).

I have them permanently mounted on the roof because we mostly beach camp. However, even on camp-outs with partial shading or cloudy days we have almost always had full batteries by the end of the day (usually by 2:PM).

We do not have LED lights. We never monitor our usage (run around turning off lights) and we use our inverter on occasion. We use our furnace set @ 70*.

We have a PWM controller and I used 10G marine wire (16' run).

I think that you will be quite happy with your set-up. Th ability to move the panels to full Sun could give you up to double my output on any given day.

As to this question:
"Ok then if question 1 = NO and 2 = YES then it seems a simple analogy could be that my batteries are a water tank. The solar panels are like a hose flowing IN to the tank. My appliances are like a drain flowing OUT of the tank. IF I have more water coming IN throughout the daytime (active power state for panels) will my batteries remain and be fully charged at the end of that daytime period? Is it that simple?"

The answer is "Yes".....it is basically that simple.

The solar array is nothing more than a battery charger. Your 12V supply to your camper always comes from the battery (unless you are 110V hook-ups).

BTW.........unless you are using 100' of cable (from your panels to the battery) 4G wire is way over-kill and will be clumsy and difficult to work with. Someone is likely to steal your system for the wire more than for the panels.

[Mr Geek]

BTW.........unless you are using 100' of cable (from your panels to the battery) 4G wire is way over-kill and will be clumsy and difficult to work with. Someone is likely to steal your system for the wire more than for the panels.

Hi Wayne,

Thanks for the feedback, great job on your installation very clean, well done. You mention you have your panels permanently installed now. From what I remember initially you had them setup so you could remove them and store them on the bed inside the RV to avoid theft while park at your apartment complex. Either way, very clean job. I based much of my decision to go with 160 watt setup after reading your posts describing how well that panel configuration worked for you. Thanks again for the helpful posts.

The 4 GA wire I was referring to is included in the installation cabling kit Cobra sells for their 1500W inverter I am installing. It's for the short run from the batteries to the inverter. They provide both 4GA and 8GA in the kit. The wire from the panels to the battery is much smaller, more like you describe you are using.

Thanks,

Bob.

[Wavery]

Hi Wayne,

Thanks for the feedback, great job on your installation very clean, well done. You mention you have your panels permanently installed now. From what I remember initially you had them setup so you could remove them and store them on the bed inside the RV to avoid theft while park at your apartment complex. Either way, very clean job. I based much of my decision to go with 160 watt setup after reading your posts describing how well that panel configuration worked for you. Thanks again for the helpful posts.

The 4 GA wire I was referring to is included in the installation cabling kit Cobra sells for their 1500W inverter I am installing. It's for the short run from the batteries to the inverter. They provide both 4GA and 8GA in the kit. The wire from the panels to the battery is much smaller, more like you describe you are using.

Thanks,

Bob.

The removable installation that I did was on my previous TM. I recently bought a 2004 2720SL. The roof A/C made the removable panels impractical (my previous TM was a '98 with side mount A/C).

I understand now about the 4G wire for the inverter. I used 2G wire for my 2500W inverter. I may not install an inverter in this camper. We only used it for popping pop-corn, heating the occasional left-overs and once or twice (in 4 years) for the hair dryer.

I have a smaller (400-800W) inverter that we plug into the 12V receptacle inside the camper. I think that we may make due with that. I just can't justify spending another $300 for a new inverter for as little as we used it.

We bought a Coleman, propane coffee maker last year and that took care of our need to use the inverter (during quiet hours) to make coffee. In fact, we no longer bring the generator with us at all anymore.

[Bill]

As Wayne says, your hose-and-tank analogy is a good one. The solar panels don't know/don't care/can't tell whether they are pushing charge into the battery or into the loads or both. The loads don't know/don't care/can't tell whether they are being powered by the battery or the panels or both.

If the loads pull less water from the tank than the panels are pumping in, then the tank will fill up (i.e., the batteries will charge). When the tank is full, the controller will throttle back the filling so the tank doesn't overflow.

There is a tendency to make electricity more complicated than it is (thank goodness! I make my living from understanding electricity!)

Bill

[Mr Geek]

We bought a Coleman, propane coffee maker last year and that took care of our need to use the inverter (during quiet hours) to make coffee. In fact, we no longer bring the generator with us at all anymore.

That's great, you must feel pretty good about spending the time and efffort in order to reap the rewards of a well configured solar system for your new RV...OH!, I hope you are enjoying your new RV, I completely missed that small detail:)

[Mr Geek]

As Wayne says, your hose-and-tank analogy is a good one. The solar panels don't know/don't care/can't tell whether they are pushing charge into the battery or into the loads or both. The loads don't know/don't care/can't tell whether they are being powered by the battery or the panels or both.

If the loads pull less water from the tank than the panels are pumping in, then the tank will fill up (i.e., the batteries will charge). When the tank is full, the controller will throttle back the filling so the tank doesn't overflow.

There is a tendency to make electricity more complicated than it is (thank goodness! I make my living from understanding electricity!)

Bill

Very good, thanks a bunch for the recap Bill. That is how I hoped and assumed it would work. I am fairly optimistic this system will be very useful and should actually be fun to "behold" the power of the sun.

Thanks again,

Bob.

[Wavery]

Very good, thanks a bunch for the recap Bill. That is how I hoped and assumed it would work. I am fairly optimistic this system will be very useful and should actually be fun to "behold" the power of the sun.

Thanks again,

Bob.

You're right.....it is "Fun". I wish that more people would view it that way. I think that too many people find Solar power to be intimidating. The reality is, it's so simple that your "Water in the tank" analogy is very fitting.

Just don't drive yourself crazy "chasing the Sun". I did that when I first set up my 1st 320W system on my sailboat in 1985. I soon realized that one adjustment per hour is all that is need for optimum performance and once every 2-3 hours is just fine. I don't adjust at all now (on the TM). They are where they are and have served me well.

[rumbleweed]

I will second Bill's comment on Arizona sun and wind. I have panels for camping and for some home use and got all my stuff from them. In simple terms, a PWM controller is simply a high speed switch. It turns on and off rapidly with the time it is on vs off being controlled by the demand (battery voltage). as a load or discharged battery presents a lower voltage, the on time is increased and current is pumped into the battery up to the panel output max. As the battery voltage increases, the amount of time the switch is on is decreased. This happens at a very high speed. An MPPT controller is somewhat like a transformer in that it takes total power into (V*A)the controller and coverts it to the charging voltage (approx 14V) at the same total power ( V*A) out which results in a higher output current than the input current. For this benefit, you will pay approx 2x the price.


The answer to your two questions depends on if he load is connected to the load terminals of the controller or the battery. If connected to the controller load terminals any demand greater than the panel output comes from the battery while any panel output not used by the load is used to charge the battery The total current available to the load is limited by the controller max output capability. If load is connected to the battery the charging is the same, but you can draw a higher output current. The controller load limit is usually very close to the max panel current capacity spec. (ie a 20W panel usually has a 20W limit on the output terminals)
I have not seen a controller that can be connected directly to a load with no battery. The controller is an electronic device that needs continuous power to operate, most panels will have times of no or limited output ( Clouds)
Depending on the device, a cloud limited output could damage the device.

[Wavery]

I will second Bill's comment on Arizona sun and wind. I have panels for camping and for some home use and got all my stuff from them. In simple terms, a PWM controller is simply a high speed switch. It turns on and off rapidly with the time it is on vs off being controlled by the demand (battery voltage). as a load or discharged battery presents a lower voltage, the on time is increased and current is pumped into the battery up to the panel output max. As the battery voltage increases, the amount of time the switch is on is decreased. This happens at a very high speed. An MPPT controller is somewhat like a transformer in that it takes total power into (V*A)the controller and coverts it to the charging voltage (approx 14V) at the same total power ( V*A) out which results in a higher output current than the input current. For this benefit, you will pay approx 2x the price.


The answer to your two questions depends on if he load is connected to the load terminals of the controller or the battery. If connected to the controller load terminals any demand greater than the panel output comes from the battery while any panel output not used by the load is used to charge the battery The total current available to the load is limited by the controller max output capability. If load is connected to the battery the charging is the same, but you can draw a higher output current. The controller load limit is usually very close to the max panel current capacity spec. (ie a 20W panel usually has a 20W limit on the output terminals)
I have not seen a controller that can be connected directly to a load with no battery. The controller is an electronic device that needs continuous power to operate, most panels will have times of no or limited output ( Clouds)
Depending on the device, a cloud limited output could damage the device.

Actually, my controller has connectors for direct output to devises like irrigation systems or other loads that you want to use during daylight hours. It also has a timer for those connections. I don't use them but they are there. I think that they are on most controllers.

http://thumbs1.ebaystatic.com/m/mwrsGkquQZ6tjGj98k94Z6Q/140.jpg

[Mr Geek]

...
The answer to your two questions depends on if he load is connected to the load terminals of the controller or the battery. If connected to the controller load terminals any demand greater than the panel output comes from the battery while any panel output not used by the load is used to charge the battery The total current available to the load is limited by the controller max output capability. If load is connected to the battery the charging is the same, but you can draw a higher output current. The controller load limit is usually very close to the max panel current capacity spec. (ie a 20W panel usually has a 20W limit on the output terminals)
I have not seen a controller that can be connected directly to a load with no battery. The controller is an electronic device that needs continuous power to operate, most panels will have times of no or limited output ( Clouds)
Depending on the device, a cloud limited output could damage the device.

Thanks Rumbleweed, great information, makes perfect sense. Recapping a bit more to further complete the understanding...

Any solar system must have a battery...period. It both powers the solar panel controller (must have some power to become active/pass power) AND it stores and outputs power used by the RV appliances (load devices).

The power from the sun/solar panels is 100% dynamic, never truly constant and can't be reliably utilized/allocated for powering many/most things. It is a FREE power source that can be stored into batteries, like RV batteries, and output in usable form for use when needed.

Being new to solar, I really appreciate all the input. It's reinforced to me that solar is pretty darn simple. The solar panels supply available power into the power storage device (battery) and the load devices (appliances) draw that power as needed. That's the system backbone.

Typical System Components:

Solar Panels

Solar Panel Controller - Passes power to batteries, switches prevent overcharging.

Battery Monitor - Displays warnings when batteries are too low.

Inverter - DC to AC - For AC power when needed. From what I can tell, inverters are power hogs, very inefficient.

I am not new to electronics, it's a huge part of many things I enjoy, always has been. But I always like to feel "familiar" with any project I undertake and this forum has been very helpful.

Another question I had was WRT sun angle versus ouput for the panels. I know Wayne has mentioned very good results with his static mounted roof panels. I also just found this middle school lesson on this topic that is actually very good. I am sure there's better information, but this is interesting reading. See attached document (the Photovoltaic Panel Simulation is a nice tool).

I have 2 - 80W portable panels coming soon (see PDF file below for the Panel Manual). They have the controller built onto each panel. I will be testing them soon with some backyard camping to see what is actually doable with winter time sunshine on these panels. I will post back with results from my backyard testing.

Thanks again for all the great information.

[Wavery]

Thanks Rumbleweed, great information, makes perfect sense. Recapping a bit more to further complete the understanding...

Any solar system must have a battery...period. It both powers the solar panel controller (must have some power to become active/pass power) AND it stores and outputs power used by the RV appliances (load devices).

The power from the sun/solar panels is 100% dynamic, never truly constant and can't be reliably utilized/allocated for powering many/most things. It is a FREE power source that can be stored into batteries, like RV batteries, and output in usable form for use when needed.

Being new to solar, I really appreciate all the input. It's reinforced to me that solar is pretty darn simple. The solar panels supply available power into the power storage device (battery) and the load devices (appliances) draw that power as needed. That's the system backbone.

Typical System Components:

Solar Panels

Solar Panel Controller - Passes power to batteries, switches prevent overcharging.

Battery Monitor - Displays warnings when batteries are too low.

Inverter - DC to AC - For AC power when needed. From what I can tell, inverters are power hogs, very inefficient.

I am not new to electronics, it's a huge part of many things I enjoy, always has been. But I always like to feel "familiar" with any project I undertake and this forum has been very helpful.

Another question I had was WRT sun angle versus ouput for the panels. I know Wayne has mentioned very good results with his static mounted roof panels. I also just found this middle school lesson on this topic that is actually very good. I am sure there's better information, but this is interesting reading. See attached document (the Photovoltaic Panel Simulation is a nice tool).

I have 2 - 80W portable panels coming soon (see PDF file below for the Panel Manual). They have the controller built onto each panel. I will be testing them soon with some backyard camping to see what is actually doable with winter time sunshine on these panels. I will post back with results from my backyard testing.

Thanks again for all the great information.

I'm not sure that it is a good idea to use 2-separate controllers on one battery bank.

The controller reads the state of charge from the battery to determine the controller's output. If you use 2-controllers on the same battery, each controller's output may cause confusion to the other controller.

I'm not sure about this and you may want to contact the manufacturer of those particular controllers. I would simply run one controller for both panels that will handle 10 or 20 amps. I have a 20A controller but you can probably get away with a 10A. You just don't want to exceed the controllers maximum rating. I would imagine that each of your panels comes with a 10A controller (I may be wrong).

As far a Sun angle is concerned +/- 15 degrees will not make an appreciable difference. after ~15* the output diminishes at a relative state of angle to the Sun. These are not "Lab-Facts", they are just my experience. Again, "Sun chasing" will get old sooner than you think.......

[Mr Geek]

As far a Sun angle is concerned +/- 15 degrees will not make an appreciable difference. after ~15* the output diminishes at a relative state of angle to the Sun. These are not "Lab-Facts", they are just my experience. Again, "Sun chasing" will get old sooner than you think.......

Hi Wayne, yes I called the dealer on this very issue, they advised these are designed to be connected as multiple units and they are simply connected all to the same place. He even recommended grouping the two connection wires into a single ring terminal connector simplifying the process. BUT I feel as you do, I want to make certain the controller will work properly and I plan on contacting the manufacturer.

I am already inline with your thinking about chasing the sun, I expect I will move these a few times a day at most. I suppose it all comes down to how much of a difference it makes. If I can get the power without moving them I won't. It sounds like you get very usable capacity from your static setup. I like that.

[rumbleweed]

Just to be politically correct, there are some controllers that can be directly connected to things such as pumps etc in remote areas, but you need to be sure that is the case. Many of the lower cost ( basic) controllers use voltage on the load side to control the charging and can get confused if there is not a battery present. Check the manual. Some of the mid range controllers actually have 4 stage charging with an equalizing mode that is time based. The key thing to remember on solar is the energy is free and portable, but collecting and storing it is relatively expensive due to efficiency.
Below is a link that will give you a fairly good estimate of the useful power you can expect from your system. You can try various angles to determine the best one and they will change from summer to winter.

http://www.nrel.gov/rredc/pvwatts/version1.html

Another calculator if you just want to calculate the angle.

http://www.macslab.com/optsolar.html

[Mr Geek]

I'm not sure that it is a good idea to use 2-separate controllers on one battery bank.

The controller reads the state of charge from the battery to determine the controller's output. If you use 2-controllers on the same battery, each controller's output may cause confusion to the other controller.

I'm not sure about this and you may want to contact the manufacturer of those particular controllers. I would simply run one controller for both panels that will handle 10 or 20 amps. I have a 20A controller but you can probably get away with a 10A. You just don't want to exceed the controllers maximum rating. I would imagine that each of your panels comes with a 10A controller (I may be wrong).......



Hi Wayne, I contacted the main dealer as printed on the panel manual I posted above and he replied with the following, regarding connecting multiple controllers to the same connection at the battery (parallel). Here is his reply:

There is absolutely no problem whatsoever using controllers in Parallel. In fact, it is standard design feature in most decent quality controllers built today. No confusion between them. You can look at the Morningstar web site and you will find most of their controllers can be used in parallel also. http://www.morningstarcorp.com/en/home. It is an easy way to add solar capacity and upgrade without having to replace your old controller with a larger one. The only precaution is that the finish voltages should be set the same, but this is factory set. Unless you use controllers from two different manufacturers, it should not concern you.
Jim Mannett - CEA Solar

[Wavery]

Hi Wayne, I contacted the main dealer as printed on the panel manual I posted above and he replied with the following, regarding connecting multiple controllers to the same connection at the battery (parallel). Here is his reply:

There is absolutely no problem whatsoever using controllers in Parallel. In fact, it is standard design feature in most decent quality controllers built today. No confusion between them. You can look at the Morningstar web site and you will find most of their controllers can be used in parallel also. http://www.morningstarcorp.com/en/home. It is an easy way to add solar capacity and upgrade without having to replace your old controller with a larger one. The only precaution is that the finish voltages should be set the same, but this is factory set. Unless you use controllers from two different manufacturers, it should not concern you.
Jim Mannett - CEA Solar

Thanks for checking on that. That's good info.

[Mr Geek]

Hello all,

First let me preface this post by saying this is not the cheapest solar solution around BUT there are real advantages to using portable, good quality, high power solar panels. For me the portable solution was the best option. Aside from using my TM for RVing/camping I also depend on my TM for emergency housing if a disaster strikes (like earthquakes here in So Cal) or the economy tanks, my TM is my “Life Boat”, it could be my home someday. So this investment into a truly powerful portable solar solution is intended to be a serious, quality and ample producing system with more than enough power to live off the grid if needed with the help of a generator on cloudy days.

So why portable solar panels?


You can camp in the shade and move them into the sun

No holes in the RV roof, easily stowed in TM curbside dinette

Useable on any 12 volt battery


As I mentioned in my initial post that opened this thread, that after reading through the TM forum and looking around online, I decided to invest in two 80 watt portable CEA Solar Panels (see manual attached). Since then I have finished installing the system and did some real-world testing. This post is to share my results, impressions and some images of this system.

The system consists of:


2-CEA Solar 80 watt portable solar panels

http://shop.rvsolarnow.com/80-watt-portable-RV-and-marine-solar-power-charger-maintainer-SLP80F-12.htm

Clipper BM-1CG Battery Monitor
http://www.clippermarineusa.com/product.php?id=39402


Xantrex Prowatt SW 1000w Inverter
http://www.xantrex.com/power-products/power-inverters/prowatt-sw.aspx

I will try to keep this summary short without mind numbing calculations and numbers. I have described my overall situation in more detail in my initial post and have attached images to this post showing key aspects of this solar power system upgrade.

For the “Do solar panels provide enough power?” question, my MAIN concern, see below:

Each panel is generating about 5 Amps in full sun of continuous power. With two panels that’s 10 Amps. If you use less than 10 Amps any surplus power is used to charge the batteries. This is very imporant, there is no wasted power, you either use it or it is stored (unless batteries are full). Also, for charging, the panel controllers use a 3-stage chargers AND the controllers are desiged to be connected in multiples, like I am doing with using two 80 watt panels. In addition, up to 4 - 80 watt panels can be used for a total of 320 watts!

Actually from what I have seen in my power use, a single panel that’s providing 5 Amps during daytime hours is probably enough for most dry campers to keep their batteries charged IF they typically conserve power. With two panels you just don't have to worry much at all unless you have cloudy days or use LOTS of power.

How much power do TM appliances use? My actual measured load (Amps) of some TM items:


Furnace 3.5 Amps
Water Pump 5 - 8 Amps
Lights (variable 0.1 Amps for LED bulb to 1.5 Amps fluorescents)
Laptop computer 4 to 9 Amps (Normal to 3D apps)
32” LCD TV 6.5 Amps


If you read through the TM Solar Panel forum you will see most people who have 160 watt solar power systems and above can easily dry camp, run the furnace as needed and use lights, and even run some high load devices occasionally and never run down their batteries. From my testing I agree with this completely. As long as you have SUN you have power. Obviously a little power management is needed to account for night time and cloudy days. Solar power is real power and it’s great to finally see a quality portable solar panel available for us RVers.

Bottom-line is I am very pleased with these CEA Solar Portable Solar Panels. They work as advertised and “FIT” the TM very well, storing perfectly in the curb side dinette seat storage area (see image). For more information on these panels see the link above and the owner’s manual attached.

One item of note, they weigh 35-lbs per panel. That adds some weight to your TM but it’s very important so they don’t blow over in the wind, it also reflects the heavy duty nature of the construction of these panels.

Overall very pleased with this upgrade for my 2619 :)

[ShrimpBurrito]

Great write-up, Bob!

Dave

[Wavery]

Bob,

For what it's worth........I used to have my panels set up as "portable" with my 2720. When we broke camp, I just laid the solar panels on the forward bunk (making sure that they were between the lights). They road there just fine and a lot less hassle.

BTW, we camped for 4 days last weekend and it was cloudy about 80% of the time. My batteries were still @12.5V (before Sunrise, the day of departure) when we left. It was ~40* at night and the furnace ran a lot. They were at 13.8V with the panels in partial Sun.

[scrubjaysnest]

looks great a little more power then we use. No tv but do have a laptop and netbook. With our power needs and only a 400 watt inverter I'm about have what your set is. Quite agree on the TM making temp housing, used the pop-up during 04-05 hurricane season cause it was cooler then the house without AC

[Mr Geek]

... An MPPT controller is somewhat like a transformer in that it takes total power into (V*A)the controller and coverts it to the charging voltage (approx 14V) at the same total power ( V*A) out which results in a higher output current than the input current...

Thanks for the explanation. Just to make sure I understand:

So basically an MPPT controller does the same job as a PWM controller but ADDS a transformer function to convert 17v into "battery friendly" 14v maintaining the same Current flow allowing it to USE this 3v PWM controllers normally cannot pass to the battery.

On an 80w panel at 17v = (4.7 Amps), this step down to 80w at 14v = (5.7 Amps) should add 1.0 Amp to the battery more than a PWM controller would. Is this accurate? How efficient are these MPPT controllers?

It seems in a large solar panel array this 3v gain per panel makes sense, but for smaller systems, until prices come down, it may not.

[Wavery]

Thanks for the explanation. Just to make sure I understand:

So basically an MPPT controller does the same job as a PWM controller but ADDS a transformer function to convert 17v into "battery friendly" 14v maintaining the same Current flow allowing it to USE this 3v PWM controllers normally cannot pass to the battery.

On an 80w panel at 17v = (4.7 Amps), this step down to 80w at 14v = (5.7 Amps) should add 1.0 Amp to the battery more than a PWM controller would. Is this accurate? How efficient are these MPPT controllers?

It seems in a large solar panel array this 3v gain per panel makes sense, but for smaller systems, until prices come down, it may not.

Muddog and I have the exact same solar panels only he has 8G wire and I have 10G, he has the MPPT controller and I have the PWM controller. We were camped together at Pt Mugu this summer and we did a test. (both arrays were flat on the roof of our TMs in full sun). I put my ammeter on both controller outputs. I was getting 8.6A and he was getting 9.5A.

We ran the test several times during the day and the MPPT controller was putting out consistantly ~10% more amps than my PWM controller.

IMO, the difference in $ might be better spent on higher wattage panels than the MPPT controller. On a large system, the MPPT controller would definitely be the way to go.

[Mr Geek]

I just wanted to say THANKS to everyone who posted to this thread. I hope the posts continue regarding all things related to Portable Solar Panels. All comments are greatly appreciated and have been extremely helpful and assisted in my successful completion of this project.

I think anyone who thinks they could benefit from solar power on their TM should definitely explore the options available to them because solar power works extremely well, it's NOT a fad or luxury. A small solar panel system adds a great new capability to the TM, self-generated REAL power for FREE.

It seems solar power has become mainstream and is more affordable and more efficient than it used to be IMHO.

All the real-world examples you will read throughout the solar power forum really tell the story of the benefits of investing in solar power for your RV.

Just today I had my panels hooked up, just monitoring them and getting used my power use versus panel power charging. At the same time I was installing a higher power 12v DC power outlet next to my inverter, using that same power source for 30 amp DC service.

I was using my inverter for AC power, I found it's much more efficient than expected. I was listening to online radio using my laptop, I had the Fantastic Fan on and needed to do some soldering. I didn't even consider plugging the RV into AC power because there was plenty of power being generated by the solar panels. I just didn't worry about running down my batteries.

Solar power provides a whole new way of thinking and opens up a new world of dry camping scenarios that use to be much less doable or desirable. That's a pretty nice feeling :D

[ShrimpBurrito]

Bob - Don't forget to check out whether you are eligible for a tax credit on those panels. I forget the IRS schedule, but I when I checked into it briefly a few years ago, panels on RVs was generally considered a qualifying expense for the credit.

Dave

[Bill]

Thanks for the explanation. Just to make sure I understand:

So basically an MPPT controller does the same job as a PWM controller but ADDS a transformer function to convert 17v into "battery friendly" 14v maintaining the same Current flow ...Almost. An MPPT controller converts extra voltage into extra current. So if your panels are putting out 17 volts at (say) 10 amps, the MPPT controller will reduce the voltage to 14 volts, but raise the current to 12.1 amps. Good stuff!

Naturally, no conversion is 100% efficient - but an MPPT controller still gets some extra charge current that a PWM controller cannot provide. This is the advantage of an MPPT controller. Whether the added charge current is worth the added cost is a different question. The usual conclusion is that in a small PV system such as those used on an RV, it is better to spend the added dollars on another panel. On a large system, the opposite is most definitely true.

Bill

[Mr Geek]

Bob - Don't forget to check out whether you are eligible for a tax credit on those panels. I forget the IRS schedule, but I when I checked into it briefly a few years ago, panels on RVs was generally considered a qualifying expense for the credit.

Dave

Thanks for the heads up Dave! I'll look into it.

Much appreciated.

Bob.

[Wavery]

Thanks for the heads up Dave! I'll look into it.

Much appreciated.

Bob.

I was going to install a 4KW solar system on the roof of my house. I looked into the solar tax credit and found that it had to be done by a licensed contractor. I don't know if the same is true on an RV but I would assume that it is.

What I found on my house was that the contractor wanted 3X what I could install it for myself. A 30% tax credit hardly justified having a contractor do it.

[Mr Geek]

Almost. An MPPT controller converts extra voltage into extra current. So if your panels are putting out 17 volts at (say) 10 amps, the MPPT controller will reduce the voltage to 14 volts, but raise the current to 12.1 amps. Good stuff!

Naturally, no conversion is 100% efficient - but an MPPT controller still gets some extra charge current that a PWM controller cannot provide. This is the advantage of an MPPT controller. Whether the added charge current is worth the added cost is a different question. The usual conclusion is that in a small PV system such as those used on an RV, it is better to spend the added dollars on another panel. On a large system, the opposite is most definitely true.

Bill

Yes, bad words on my part, I meant same POWER...Doh! I assume POWER is always Volts, Watts and Amps. And the law is Watts = Volts x Amps. So when one variable changes another must also for the law to remain true.

Thanks for the clarification/correction. I suppose someday MPPT controllers will become the norm due to their energy efficient nature. I agree $$$ is better spent for another panel on RV applications.

[fourteener]

I just purchased a 100 watt portable solar panel and it is being shipped. I have been reading all of the info on the forum, and have a few questions.

1) It is best to have the PWM controller as close to the battery as possible, is that correct?

2) Sounds like everyone has settled on 10 awg wire from the panels to the controller, and 8 awg (short run) from the controller to the battery, correct?

3) For the wire which is best, speaker, automotive, or marine? And why?

4) In-line just prior to the battery, there should be a fuse added, what amp fuse is recommended - 30 amp? Also, does that need to be on both the + and - sides or just one fuse on the + side?

5) What quick connectors does everyone feel are best? Anderson Powerpoles 30 or 45 amp, bullet/automotive SAE connectors like the ones on battery tenders, MC4, or something I haven't mentioned.

Any other info that I haven't thought of is appreciated. - Thanks Again!

[Riwright]

1) It is best to have the PWM controller as close to the battery as possible, is that correct?

Shorter wiring runs are always better. I don't think it makes a lot of difference whether it's panel-to-controller or controller-to-battery. Just make the wires as short as you can.

2) Sounds like everyone has settled on 10 awg wire from the panels to the controller, and 8 awg (short run) from the controller to the battery, correct?

That should work fine.

3) For the wire which is best, speaker, automotive, or marine? And why?

I would use marine wire. It is tinned and that might save you some corrosion problems. Ebay has some good deals.

4) In-line just prior to the battery, there should be a fuse added, what amp fuse is recommended - 30 amp? Also, does that need to be on both the + and - sides or just one fuse on the + side?

Just the positive side. The fuse should handle all the current your panels can put out under ideal conditions. 30 amps at 12 volts is 360 watts so a 30 amp fuse should do fine.

5) What quick connectors does everyone feel are best? Anderson Powerpoles 30 or 45 amp, bullet/automotive SAE connectors like the ones on battery tenders, MC4, or something I haven't mentioned.

I've used automotive bullet connectors but I'm not that happy with them. Corrosion. I'll be interested to hear suggestions from others.

[scrubjaysnest]

I just purchased a 100 watt portable solar panel and it is being shipped. I have been reading all of the info on the forum, and have a few questions.

1) It is best to have the PWM controller as close to the battery as possible, is that correct?

2) Sounds like everyone has settled on 10 awg wire from the panels to the controller, and 8 awg (short run) from the controller to the battery, correct?

3) For the wire which is best, speaker, automotive, or marine? And why?

4) In-line just prior to the battery, there should be a fuse added, what amp fuse is recommended - 30 amp? Also, does that need to be on both the + and - sides or just one fuse on the + side?

5) What quick connectors does everyone feel are best? Anderson Powerpoles 30 or 45 amp, bullet/automotive SAE connectors like the ones on battery tenders, MC4, or something I haven't mentioned.

Any other info that I haven't thought of is appreciated. - Thanks Again!
For 1 & 2 the answer is yes. Or like Bill did; a 10 awg extension cord with the ends cut off. 30 feet is going to be about your limit for 10 awg.
For 3 use marine, it's the most flexible and pre tinned for soldering.
4 Don't use an in line fuse, use a circuit breaker in the plus lead. In line fuses develop a little volt drop which A results in failure and B loss of power to the battery. For a 100 watt panel a 15 amp circuit breaker will be fine but you may add a second panel so maybe a 30 amp if you do.
5 MC4 is the most common in solar applications they have good surface contact and o ring sealed. The rest of the connections should be ring lugs crimped and soldered.

[fourteener]

I should have stated first what I'm thinking about doing, to make the best use of your knowledge base. The portable unit that I've purchased comes with the controller mounted to the back of the panel. Depending on how it is mounted, and reading prior post, I thought it would be best to see if I can remove and relocate the controller at the battery box. It seems there are some inconsistencies surrounding how important this move is? So which is better,,,,

Option 1: removing and relocating the controller to the battery box,,,,,
or
Optioin 2: simply leaving it attached to the panel

Also, are there any recommendation as to what type of breaker to use?

Most importantly, I want to stop again, and thank all our you for this knowledge sharing,,,I hope some of my carpentry or fabricating skills can be half as helpful at some point.

[Redtail Cruiser]

Fourteener, i am also gathering the materials to do an install for a portable solar system on my TM. I am mounting a 6x6x4 inch weather proof electrical junction box on the tongue frame next to my battery boxes. Inside this box will be a battery disconnect, a 15 amp circuit breaker and my solar controller. My 100 watt solar panel will be able to set either on the roof of the TM when camping or up to 30 ft. away from the trailer if shaded. At home the panel will set on the roof of my south facing shed to keep the batteries up during storage.

When completed, I will post a description and photos of this mod.

[fourteener]

Redtail Cruiser, Very interested in your setup and lessons learned. Please post a link to the type of circuit breaker you are going with. Also any specific reason why you are using 15 amp instead of something larger. I want to ensure I protect the TM, but don't want an overly sensitive system either? Also, does the controller produce any heat doing the voltage downgrade, as it may (as well as the breaker) which could overheat inside the weatherproof box? I'm not sure if it needs to 'breathe' or not? Although I do like the idea as I like how clean it would make it look. Also, I read somewhere that most all PWM controllers are waterproof. I've noticed that us TMers tend to overbuild things, which is not always a bad thing. Seriously curious as to picking your brain on all aspects of this project.
Here's an article I came across when gathering intel:
http://www.sebsgarage.com/camping/portable-solar-charger/

[scrubjaysnest]

The purpose of mounting the controller as close to the batteries as possible is temperature compensation. The better controllers use this to properly charge the batteries. The ideal is an external temperature probe attached to the battery case.
Circuit breakers are available at any auto parts store or marine place. For the one between the controller and battery mine is auto reset.
My circuit breakers are all mounted in plastic wall mount electrical boxes, the same as I did in the pdf instruction at this link http://www.trailmanorowners.com/forum/showpost.php?p=80923&postcount=63

[Bill]

Fourteener -

The location of a PWM controller - near the panel or near the battery - does not matter since the current is the same everywhere in the circuit. This is not quite true for an MPPT controller, but location is not critically important there, either.

A PWM controller should not heat up, since it is a switch rather than a resistor. There are small losses, and hence a very small amount of heating, but as long as there is free air around it, it should be fine. This is in contrast to an old-fashioned linear regulator, which could heat up considerably. I'm under the impression that these are no longer made, for a number of reasons including heating.

First and foremost, a fuse or circuit breaker is sized to protect the wiring. A 15-amp breaker is good for #14 wire or larger, but not for a smaller size. As a secondary objective, the breaker may be sized to protect the controller. If so, the controller's manufacturer will specify a breaker rating, but the wire size must still be chosen so that the breaker protects it.

Hope these help.

Bill

[Redtail Cruiser]

Fourteener, after researching portable solar systems and getting alot of conflicting info, I decided to call my local solar company. They were the installers of the solar system that Sungevity put on my home. I explained to them what I was looking for and how I intended to use it. They are putting a system together for me that will include a 100 watt (two 50 watt foldable panels), a 15 amp PWM controller, a 15 amp circuit breaker with a marine cover mount and 30 ft of #8 AWG extention cord with weather tight twist lock connectors. The controller will be mounted with stand off mounts in the J-box and I have been told that heat build up won't be a factor with this controller.
They are giving me a pretty good deal ($250) since I'm a repeat customer and had given them a referal for a neighbors system last year.

[fourteener]

Bill / Tim / Scrubjaynest,

Thank you so much for all of your input.

I think I'm planning to go with:
1) 25-30 ft of 10 AWG Marine wire from the 2-foldable 50 watt (100 watt total) solar panels.
2) If the controller is easily removed from the panels, I think I'll move it so that it is next to the batteries, to limit the potential for loss voltage that could occur over the 25-30 ft extension run.
3) Set up some type of waterproof junction box near the battery box with the cotroller and a 15 or 30 amp circuit breaker, and 1-3 ft of 8 AWG Marine wire (as short as possible) to the battery.
4) One quick connector near the controller (between the extension and the controller), I am thinking about going with 45 amp Anderson Powerpole Connectors.
And I should be ready for some hardcore camping. Thanks Again :)

[TM Pilot]

Are any of these worthy?

http://www.eco-worthy.com/catalog/folding-solar-panel-c-71_61.html

[Bailey'sMom]

Can I add a portable solar panel to my existing factory installed solar panels and if so how can I do this? Is there a way to connect the two via 12 volt cigarette type plug?

There are some times that my camper is in the shade or only limited sun with no way to get the panels in the full sun. Thus I would like to be able to be able to plug in an extra panel to help charge the battery.

I have a solar panel my dad used to use to charge his batteries. Don't know how many watts it is, but it was portable and I believe it was plugged in with 12 volt plug.

[scrubjaysnest]

Can I add a portable solar panel to my existing factory installed solar panels and if so how can I do this? Is there a way to connect the two via 12 volt cigarette type plug?

There are some times that my camper is in the shade or only limited sun with no way to get the panels in the full sun. Thus I would like to be able to be able to plug in an extra panel to help charge the battery.

I have a solar panel my dad used to use to charge his batteries. Don't know how many watts it is, but it was portable and I believe it was plugged in with 12 volt plug.
What ever panel you decide on it has to be wired in parallel with the existing panel at the controller input. As for the cigarette light plug it can be used but it would be better to use the MC4 connectors used in solar panel connections. Other options that are also more durable then a cigarette lighter plug would the ATV winch style power connectors or a trolling motor plug and socket. Make sure the extra panel comes with isolation diodes to prevent the two panels back feeding each other.
This set up will work but you will only gain a little over the single panel. The panel in the shade is the problem as it will tend to pull down the total voltage available to the controller. An example is The panel in shade has 12 volts output and the one in full sun is at 14 volts say. The controller will sense about the average of the two, or 13 volts. This results in less current to charge the battery.

We try to keep both our panels in full sun but in the east that is hard to do.

If your budget can handle it get a panel equal to or larger then your existing one.

[Bailey'sMom]

What ever panel you decide on it has to be wired in parallel with the existing panel at the controller input. As for the cigarette light plug it can be used but it would be better to use the MC4 connectors used in solar panel connections. Other options that are also more durable then a cigarette lighter plug would the ATV winch style power connectors or a trolling motor plug and socket. Make sure the extra panel comes with isolation diodes to prevent the two panels back feeding each other.
This set up will work but you will only gain a little over the single panel. The panel in the shade is the problem as it will tend to pull down the total voltage available to the controller. An example is The panel in shade has 12 volts output and the one in full sun is at 14 volts say. The controller will sense about the average of the two, or 13 volts. This results in less current to charge the battery.

We try to keep both our panels in full sun but in the east that is hard to do.

If your budget can handle it get a panel equal to or larger then your existing one.


Thanks Scubjaysnest.

You've convinced me that it's too complicated for me. Guess I will have to find a way to keep them in decent sunlight.

[TM Pilot]

Here is 100watt foldable solar suitcase for $269

http://www.renogy-store.com/100W-Suitcase-p/kit-stcs100d.htm
http://renogy.com/wp-content/uploads/2013/12/RNG-F-2X50D-R.1.pdf

[tentcamper]

Just order a 80W fordable. Was thinking about 100W, but since the 80w is a little smaller in size. I figured I would go with it. We are very conservative with our battery. During the summer for years we can go 7 days between charges on our G31 battery. During the spring and fall if we are running the furnace we get 2 to 3 nights. Most of our dry camping in the spring and fall are 3 nights with a few 4-5 nights.

My thoughts are to stretch the recharging to 5 day. So I think an additional 20 amp per day on average will do it for me. I think on average a 80 watt panel should have no problem giving me the 20 amps. Worst case I might need an additional 40w panel.

[flipflop]

http://www.trailmanorowners.com/forum/attachment.php?attachmentid=5393&d=1291851573http://www.trailmanorowners.com/forum/attachment.php?attachmentid=5393&d=1291851573

I'd like to know where these connectors can be acquired. Pretty slick.

[gonzo628]

I'd like to know where these connectors can be acquired. Pretty slick.
aren't they just the quick connects for battery tenders? http://www.batterytender.com/Accessories/6-ft-Extension-Lead.html

[Jampcourt]

We bought a 100 W Renogy portable solar panel (with controller), and a 25 foot cord from the manufacturer, and then hooked a 7 pin plug to the end of that cord so we don't have to access the battery directly. It was an easy solution that works really well for us.....if the fixed panel is in the shade, it is a simple matter to position the portable and plug in to the front end of the trailer. Kept us whole all summer! (Our battery is in the front, under the sofa). We do probably lose some energy through the long cord, but it still works just fine. DH can provide details if anyone is interested.

[tentcamper]

Those connectors are call TP quick disconnect connectors. I got 5 sets on amazon that are 10 gauge wire. They were called "TP-10 CB Radio Polarized Quick Disconnect"

I use them to connect my portable panels. I don't seem to have any loss on current flow. I did not use battery tender one I had on my battery because it is to light. I made one for the battery so I had 10 gauge going to the battery.

[flipflop]

Those connectors are call TP quick disconnect connectors. I got 5 sets on amazon that are 10 gauge wire. They were called "TP-10 CB Radio Polarized Quick Disconnect"

I use them to connect my portable panels. I don't seem to have any loss on current flow. I did not use battery tender one I had on my battery because it is to light. I made one for the battery so I had 10 gauge going to the battery.

Thanks, yah, needed 10AWG instead of the battery tender ones referenced above which are smaller. I did want those covers also.

I found some 18AWG battery tender types on e-bay with the covers, so maybe I'll buy both then put the covers on the 10 guage.

http://www.ebay.com/itm/10-Gauge-2-Pin-Quick-Disconnect-Wire-Harness-SAE-Connectors-/121251351255

http://www.ebay.com/itm/BATTERY-TENDER-QUICK-CONNECT-CABLE-W-SAE-2-PIN-RING-TERMINAL-HARNESS-DELTRAN-/161089041262

[gonzo628]

yep, looks like I missed that (wire size issue). I just recognized the connectors as the same ones I use for my battery tender on my motor cycle.

[flipflop]

Question - Renogy Commander MPPT charge controller and the TM has two 6v batteries in series.

Do I connect the MPPT positive to the positive terminal on one battery, the MPPT negative to the negative on the other battery? Or can I just connect both MPPT + and - to the same battery?

[BradS7535]

Question - Renogy Commander MPPT charge controller and the TM has two 6v batteries in series.

Do I connect the MPPT positive to the positive terminal on one battery, the MPPT negative to the negative on the other battery? Or can I just connect both MPPT + and - to the same battery?

Separate batteries. + On one, - on the other, but make sure it's the correct + and - on each...there should be a wire connecting + of one to - of the other to connect them in series...you'll want to connect the MPPT to the other + and -.

[tentcamper]

Is that controler made to charge a 12V battery? If so, you need to connect the + to the positive terminal that go's to the camper positive wire and connect the - to the other battery's negative terminal that is connected camper negative (ground) wire.

[flipflop]

Alright, thanks for the replies. I'll see what cabling changes are needed tomorrow AM.

[rickst29]

Is that controller made to charge a 12V battery?
Yes - Renogy is reselling EP Tracer model 'BN' MPPT controllers with Renogy 'Commander' labels on them. (Models 'BN' are the newer, better ones for Negative Ground configurations, like the TM.) Renogy also sells an older (and worse) 'Tracer' model as product ID "RNG-CTRL-MPPT20". I can recommend the 'Commander' models and their OEM equivalents. I do not recommend buying the older product line.

(I've used the 20A 'BN model in testing the 'Tow Vehicle as a Big Solar Panel' charge source swapping circuitry. It's tuning parameters , performance, monitor capabilities, and durability seemed pretty good. About the only thing it doesn't offer is a push-button to invoke "Boost Mode" by operator command, on either the Controller or the Remote.)

[TMfor4ofus]

subd