Solar Installation FAQ

[BradS7535]

So I've been reading through all the solar install threads and I still have a few questions I'd like to get everyone's input on.

Series vs Parallel

So from my reading, I understand the basics of the differences between the two.

Series works better if you have mismatched panels
Panel voltages add in series, current remains the same
Panel current add in parallel, voltage remains the same
Series more susceptible to shading degradation
Series = MPPT Parallel = PWM or MPPT


Obviously you can have a combination of series and parallel to fit your needs, but my basic question is what is the more popular method here? I am sure there are specific circumstances where one method is better than another, but from an "overall" perspective which is the more robust/efficient way? Do you get much more out of a parallel system with MPPT over using a PWM? If your camping habits are a mix of full sun and partial shade.

Also, it seems most of the installs here have the batteries located in the back compartment, which makes for a nice rear shell install. What about if your batteries are on the tongue? Where do you install the controller (assuming not weather-proof)? Do you prefer front or rear shell with batteries on tongue?

I would like to contribute a nice technical FAQ/Install guide for the Tech Forum combining all the information in all the different install threads and this one to be a 1-Stop shop for future solar installs, instead of reading through the various threads.

My main question and point of internal debate is which of the following 3 options is the best overall assuming cost isn't a huge driving factor (<$200 cost difference).

1) Series w/ MPPT
2) Parallel w/ MPPT
3) Parallel w/PWM


Note: I still haven't quite figured out the inverter part of the equation yet, I'll get to that later, so lets leave that out of this discussion (unless adding an inverter is a large factor of which design to go with)

[Padgett]

Can treat inverter entirely separate, mine is in the cabin storage compartment under the bed so a very short run of AWG #2 through a 100A circuit breaker to the batteries (my travel Keurig pulls 64A for about 3 minutes. I have a 1KW continuous inverter.

Nice thing about panels on the rear module is that they shade the bed area.

I have 200W of mono through a 30A PWM controller that worked just fine at Sun'n'Fun this year.

Was building on what I had (including the WFO) and if building from scratch would have a much more integrated installation and 300W of panels.

From a location standpoint if had front batteries I'd be very tempted to move it all to the rear, the two compartments under the bed are just so handy and share a common bulkhead. The run to the converter is also short.

The other consideration is whether you need/want AC while dry camping. I consider that essential but not all care.

[LoveToCamp]

On my 2417 Sport, the batteries were on the tongue. I installed the panel on the rear panel, as it was easier to adjust for the added weight. I ran the #10 wire to the PWM controller, which I mounted on the front of the lower box. This was protected from weather by the shell when closed, and protected by the open shell when camping. Pics are in this thread (http://www.trailmanorowners.com/forum/showthread.php?t=13865&page=4), post #37.

When we got our 2014 2417, I installed one 100w panel on the back shell, as that is where it fit best. My battery is under the dinette bench, which is in the front slide. The PWM controller was installed at the TM factory, and is under my sink, by the entry door. About 10' of wire run to get to the battery, and 18' of wire to get to the solar panel.

I camp dry all the time, and have not run out of power, even in winter when I run the furnace through the evening, and overnight. I am almost fully charged every evening, even when camping amongst trees (Rocky Mountain tree cover is not as dense as coastal/eastern cover). I added a second panel and a second battery last year, and am very happy with my parallel panel installation.

In the thread linked above, there is discussion about MPPT vs PWM. Most conclude MPPT is not worth the money for the systems we can install in our TMs. Larger trailers where you can mount 400+ watts of solar are worth the MPPT installation. We don't have enough room on our roof, according to those who have done the research, to warrant the expense of MPPT. But, others will recommend MPPT, as they have a different measure of benefit.

[BradS7535]

Padgett/LoveToCamp,

Thanks for your input.

One thing I am trying to determine as well in regards to MPPT vs PWM is the effect on overall system cost/value.

I read the post from rickst29 about the difference in efficiency between the two, but I'm a bit confused as to how to calculate the benefit of a MPPT in terms of output current.

Assume perfect/ideal conditions, same configuration (parallel), same solar panels (say 2x100W) (Vmp = 18.9, Imp = 5.29) and what you get out of MPPT vs PWM.

PWM will pulse to get down to the charging voltage of 14.5V with all the amps (5.29*2) so P=V*I, 14.5 * 5.29 * 2 = 153.4W. So I'm paying for 200W + PWM controller and I am actually "getting" 153.4W with 10.58A going to the batteries.

I'm trying to figure out how to calculate the same with an MPPT controller. With the same setup the panels will put out 18.9V (higher than the needed 14.5V) with a total current of 10.58A. Am I correct in assuming that with the MPPT controller I'll "get" the full 200W, which means P/V=I, 200/14.5 = 13.8A? The excess voltage above 14.5 is getting converted to extra amps. So I'm paying for 200W+MPPT controller and I'm actually "getting" 200W with 13.8A going to the batteries?

In a series configuration with MPPT I'm not sure how to calculate the actual current out. In rickst29's example the MPPT had a maximum current output of 15A which led to 217W. The panels were only 200W, so how would I calculate the current output from that system (I'm assuming its less than 15W).

I'd like to try to calculate $/Watt and $/Amp to see the normalized cost difference between the two.

[LoveToCamp]

There are some solar/electric experts, which I am certainly not, on the forum. A good thread is this one (http://www.trailmanorowners.com/forum/showthread.php?t=16269), if you have not been there, yet. The experts discuss much more than I care to think about. I know my setup works, and it cost about $250, plus whatever TrailManor charged me for my PWM controller (which I am quite happy with).

My batteries (I added a second one, as one was dead the day before I was leaving on a trip. Got a replacement, and shop told my my old battery was fine, just discharged - phantom loads, or parasitic drain) have plenty of juice to do the job every day, even when we camped in Utah with overcast skies and rain most of the week. Single panel/single battery worked fine on an earlier trip, with panel in full shade all day, and much of many days being overcast. I can't justify an MPPT controller, based on my experience.

[scrubjaysnest]

In simple terms, the cost per watt break even point is about 400 watts of solar.
Below that MPPT isn't worth it. A quality Morningstar MPPT for 400 watts is about $400, for a PWM it's about $150.
Series panels require MPPT.
Under real world conditions it will be hard to tell the difference in MPPT vs PWM at 400 watts of parallel panels.

[BradS7535]

So I talked to Renogy tech support and they said that a MPPT is about 97% efficient at converting excess voltage to extra amps.

So a simple "ideal" comparison for my example above would be:

PWM (Parallel):
5.29*2 = 10.58 charging amps

MPPT (Parallel):
(5.29*2) + .97*(18.9V-14.5V) = 14.85 charging amps

MPPT (Series):
5.29 + .97*(37.8V-14.5V) = 27.89 charging amps

You can see that the MPPT is much more useful in series rather than in parallel, so in a parallel application it doesn't make much sense cost-wise to go to MPPT.

However, I've been looking at different panels/controller combinations and found an interesting option.

Single 250W 24V panel w/ MPPT controller, Voc=37.5V, Isc = 8.87A, Vmp=30.1V, Imp=8.32. Using a single 250W panel with a MPPT controller will give me: 8.32 + .97*(30.1V-14.5V) = 23.45 charging amps.

Unfortunately the charge controller has a maximum output current of 20A, but with cable losses and everything else realistically I'll probably be getting slightly less than 20A anyways.

The cost between a 2x100W PWM system and 1x250W MPPT system is about $130, but I am getting more charging amps out of the 250W system. The $/amp is cheaper on the 250W system.

Let me know your opinions or if I've got anything incorrect here.

[Dchisenh]

One of the biggest things to consider is what type of batteries you have or are planning to get. A lot of the cheaper MPPT controllers out there can't adequately charge the popular Trojan T-105's at 14.8 like the manufacturer recommends, so while you might be getting more amps, it's not as 'healthy' for your batteries at the lower volts. Once you get into the MPPT controllers that are user adjustable, you're talking a pretty penny that might put the setup out of your budget.

You're doing your homework and getting into the nitty-gritty, so kudos for that!

From what I've seen, solar setups usually fall into one of two categories: 1) the minimum to keep batteries and systems working while camping for a few days or 2) the maximum with a large/unlimited budget and the best/greatest/newest components out there. If you're in the first group (like most folks are), a few panels, short wire runs to minimize line loss with parallel arrays, and a PWM controller are more cost effective. If you've got the money to blow or are going boondocking for a very long time/indefinitely using a large battery bank, large and/or high voltage array setup in series (negating line loss that way), an MPPT controller is the way to go.

If I won the lottery, I'd get some lithium batteries, a Morningstar Tristar 60 MPPT controller and as many panels as I could realistically fit!

So, all that said, at this early stage of planning, I'd suggest you first figure out what your loads will be, get enough batteries to support that and then figure out what panel/controller combo will allow you to feed them taking into consideration roof-space/wire runs/budget.

-Dan

[scrubjaysnest]

Don't forget that is based on ideal conditions of full sun and panel temp of 77 deg to 80 degs where they test them in a lab. Real world with full sun and and temps in the 40's you will go well over the 20 amps of the controller. Length of the wire impacts voltage not current with and end result of lower wattage. Real world expect 77 to 80 % for the controller efficiency.
Real world you need about 140 watts of solar per 100 Ah of battery and while GC-2's prefer about 22 amps at 14.8 volts always figure your solar size at 14.5 volts as a rule of thumb.

[BradS7535]

Thanks for the info. The inner nerd in me always wants to get the best or at least make the best out of what I have. Hate knowing I paid money for 200W but I'm only getting less than that with a PWM controller. But then again gotta think practically and economically.

Out of the installs here: PWM or MPPT and where did you install your controller (if not in the rear storage compartment)?

[jswinner]

On my 2417 Sport, the batteries were on the tongue. I installed the panel on the rear panel, as it was easier to adjust for the added weight. I ran the #10 wire to the PWM controller, which I mounted on the front of the lower box. This was protected from weather by the shell when closed, and protected by the open shell when camping. Pics are in this thread (http://www.trailmanorowners.com/forum/showthread.php?t=13865&page=4), post #37.

When we got our 2014 2417, I installed one 100w panel on the back shell, as that is where it fit best. My battery is under the dinette bench, which is in the front slide. The PWM controller was installed at the TM factory, and is under my sink, by the entry door. About 10' of wire run to get to the battery, and 18' of wire to get to the solar panel.

I camp dry all the time, and have not run out of power, even in winter when I run the furnace through the evening, and overnight. I am almost fully charged every evening, even when camping amongst trees (Rocky Mountain tree cover is not as dense as coastal/eastern cover). I added a second panel and a second battery last year, and am very happy with my parallel panel installation.

In the thread linked above, there is discussion about MPPT vs PWM. Most conclude MPPT is not worth the money for the systems we can install in our TMs. Larger trailers where you can mount 400+ watts of solar are worth the MPPT installation. We don't have enough room on our roof, according to those who have done the research, to warrant the expense of MPPT. But, others will recommend MPPT, as they have a different measure of benefit.

Love to Camp:
Which 100 watt panel are you using? Did you find one narrow enough to fit without overhanging the rear? And did you mount it centered across the back of the rear shell?

Thx

[LoveToCamp]

I purchased (separately) two 100w polycrystalline panels from WindyNation.com. I got an idiot-light PWM controller in 2012 when I purchased my first kit. That controller is no longer available, as more-advanced controllers are now part of the kits.

Also, there appear to be three or four 100w kits available, now, so my kit is not apparent out of the selections. Plus, you can get two panels in one kit now, which saves some money.

My first panel I mounted on the rear shell, but did not center it. I on the street side, as that corner gets more sun when I have the TM next to the house for storage (I cut a hole in my cover, so it gets sun daily). It does not hang over the rear. You could center it, no problem. Just run the wire along the roof right behind the front shell, so it gets less wind on the highway.

I put the second panel on the front shell, on the curb side. This will allow me to put a third panel (also on the front) into the system, if I want. So far, no need at all for a third panel.

[BradS7535]

If you could get a 250W 24V panel for essentially the same price as 2x100W 12V panels, would you go with the 250W even if it meant needing to upgrade to a MPPT controller?

[BradS7535]

Since CustomRV still has my TM, does anyone know the dimensions of the exposed portion of the rear shell (when closed)? Trying to determine what size panels will fit up there and in what orientation.

[Bill]

To answer that question, we know to know what model TM you have. Why not add it to your signature line?

Bill

[BradS7535]

To answer that question, we know to know what model TM you have. Why not add it to your signature line?

Bill

Figured everyone was physic here!

[Padgett]

That's easy: Renogy 100W monos. I have two, figure three would fit.

[BradS7535]

Anyone with batteries on the tongue with solar? Where did you install your charge controller? I know you want the controller as close to the batteries as possible, but what is a reasonable length between the two?

[LoveToCamp]

My first TM had the battery on the tongue. I installed the controller on the outside of the front of the box. It is covered by the front shell while traveling, and sheltered from weather by the front bed/shell when set up for camping. I had about 3' of wire between the controller and the battery. Can't get much closer than that!

If you put your panels on the front shell, it is not too long of a run from your panels to the controller.

[BradS7535]

My first TM had the battery on the tongue. I installed the controller on the outside of the front of the box. It is covered by the front shell while traveling, and sheltered from weather by the front bed/shell when set up for camping. I had about 3' of wire between the controller and the battery. Can't get much closer than that!

If you put your panels on the front shell, it is not too long of a run from your panels to the controller.

I've seen the photos of your install and it looks good, however I'm concerned that if I decide to go with a MPPT, or the PWM isn't weatherproof, it might not be a good idea to install on the outside (even if it is covered when closed and covered by the bed when open. Im also considering a single 250W panel which will probably only fit on the rear shell. Even if i went with 2x100W panels, with the A/C, TV antenna and vent I'm not sure there is room for the 2 on the front shell.

[Kidkraz]

Brad,

My battery is on the tounge it came that way from the factory with an 85 watt solar panel installed. All I have to see what's happening with my system is this panel, again installed by the factory.

[LoveToCamp]

kidraz's post makes me ask the question - in layman's terms, what is the impact of a 12' run of 10ga wire from the controller to the battery, vs. a 3' run? My controller is on the wall inside my door, as it appears kidraz's. Not real close to the battery (I ran under the TM, then in the front of the slide to get to the battery under my dinette seat).

Wonder if it has a noticeable impact, or just one that is measurable, but not significant?

[BradS7535]

Brad,

My battery is on the tounge it came that way from the factory with an 85 watt solar panel installed. All I have to see what's happening with my system is this panel, again installed by the factory.

I think your controller and monitor are all in one. If you looked on the inside of that cabinet at the back of that monitor panel I bet you would see 4 wires, 2 going to your solar panels and 2 going to your battery.

I was thinking that is where I would install my controller, in the cabinet next to the fridge.

LoveToCamp, that is the essence of my question as I will probably have about a 10' run from inside to the battery. Want to know if it makes a big impact.

[BradS7535]

Ok, so looking for the electrical experts to chime in and let me know what they think of my proposed setup below. Hopefully my research has paid off.

Questions:
1) Can I use circuit breakers to combine the functionality of a fuse and a cut-off switch?
2) Based on my equipment below, did I size the breakers appropriately?
3) Is a fuse/breaker needed from the battery to the TM, if so what size? I know many of you have installed the battery cut-off switch, but do you also have a fuse there? If a fuse is needed, can I use a breaker to combine fuse and battery cut-off?

Equipment:
1 x Renogy 250W Panel (http://renogy.com/renogy-250-watt-24-volt-monocrystalline-solar-panel/)
1 x Tracer 3215BN MPPT (http://www.epsolarpv.com/en/index.php/Product/pro_content/id/573/am_id/136)
1 x 10A Circuit Breaker?
1 x 40A Circuit Breaker?
1 x Battery Cut-Off switch (or breaker?)
10AWG wiring

[Padgett]

I understand your reasoning but used a pair of 30A circuit breakers not a 10A and 40A. for two 100W cells in parallel.

Also used 2ga wiring and a 100A CB for the 1KW inverter line. (Coffee maker pulls 64A of12v - 770W of 120VAC).

[Bill]

Questions: <snip>
3) Is a fuse/breaker needed from the battery to the TM, if so what size? I know many of you have installed the battery cut-off switch, but do you also have a fuse there? If a fuse is needed, can I use a breaker to combine fuse and battery cut-off?

Yes, a fuse is needed, and TM wired one in when the trailer was manufactured. If it is not there, you need to add one. This is completely independent of whether you have solar or not, and independent of whether you have a battery cutoff switch or not. The fuse must be within a few inches of the battery - do not try to move it into the circuit breaker box in the converter.

To look for it, follow the wire from the battery positive post toward the TM about 8-10 inches. You should/must encounter a fuseholder. The value of the fuse is 30 amps, and should not be changed. Take a look at this picture in my Tech Stuff album. If you have the first type of fuseholder, you should change it out to the second type. The change is easy - you can find the automotive fuseholder at WalMart or any hardware or big box or auto parts store.

http://www.trailmanorowners.com/forum/album.php?albumid=8&pictureid=760

Bill

[BradS7535]

The fuse must be within a few inches of the battery - do not try to move it into the circuit breaker box in the converter.
Bill

Bill, in my circuit diagram I have a battery cut-off switch, but I'm not showing a fuse. If the fuse is there would it be possible to swap the fuse with a 30A circuit breaker that would combine the 30A fuse with a battery cut-off, or is it better to just keep the current 30A fuse (assuming it is the blade type) and add a battery cut-off switch?

[BrucePerens]

NEC since 2008 has required a DC GFI on solar panels installed on homes. I expect to connect enough to get to 150V, so it makes sense.

Midnite solar makes this (http://midnitesolar.com/productPhoto.php?product_ID=185&productCatName=Breakers&productCat_ID=16&sortOrder=2&act=p) GFI. Amazon has the 80 amp one for less than the 63 amp one here (http://www.amazon.com/MidNite-Solar-Ground-Breaker-150VDC/dp/B00BSYSYS2). You could put this in series with a properly-sized DIN breaker. You'd need a waterproof DIN breaker enclosure to mount them, like this (http://www.internationalconfig.com/icc6.asp?item=4QEL), but I don't have a good U.S. source.

As you can see, nobody's really produced the right product for RV use. This really belongs on the roof with the panel, before any flexible wire run.

[klpauba]

Since you have only a single panel, I would think that any circuit breaker (or even a switch) that is rated a 125% or more of the short circuit current rating of the panel will suffice. Many sources (Midnight Solar was one of them) mention that no overcurrent protection is required for a series-connected PV array. If you have 3 or more parallel-connected PV panels then overcurrent protection is mandatory.

I've also read that if you're using an MPPT controller (which you've mentioned that you are), you don't need to protect the solar panel wiring from the battery since the MPPT controller will not pass current to the panel connections in a failure condition. This is not necessarily the case for PWM controllers.

I will not argue Bruce's point that DC GFI would be desirable especially at the voltages he's talking about.

I merely bring this up for discussion since I'm sharing what I've read (on the internet, no less) and I'm an engineer, but not an electrical one. I could very well be wrong (and welcome the critique by those more knowledgeable).

[Padgett]

My solar panels have built in diodes to prevent reverse or excessive currents.

[BrucePerens]

Padgett,

Some panels and some junction boxes have bypass diodes. It's not at all clear to me that the bypass diodes limit current or block reverse voltage. They only bypass current flow around cells that are in darkness. The cells themselves might have some inherent current limiting and reverse resistance.

Silicon photovoltaic cells have high resistance in darkness. In case a panel, or part of a panel, is shadowed by something, it can prevent all series-connected cells from delivering any current. To prevent this from happening, bypass diodes are used. Bypass diodes are connected in parallel with a bank of cells. They appear to be reverse-biased from the perspective of the bank, but forward-biased from the perspective of all banks connected in series with that one.

On my panels, there is an internal bypass diode for each of three series-connected strings of cells within the panel. So you can just plug them together in series, as long as the series voltage and current doesn't exceed the ratings of the diode, without any need for a junction box except for the end connections. Some panels don't have internal diodes, and then diodes within a junction box are necessary.

One of the failure modes of cells is that a portion of a cell can be reverse-polarized with regard to the rest of the cell. This creates a hot spot.

[BradS7535]

Can someone explain when a fuse/breaker is needed and where for solar? I'm a bit confused now as to the purpose and if I actually need one between the panel and CC or CC and battery. If I don't need a fuse/breaker I'll just put a switch to disconnect the solar.

[klpauba]

See https://www.windynation.com/jzv/inf/how-properly-fuse-solar-pv-system

Commercially made solar panels over 50 watts have 10 gauge wires capable of handling up to 30 amps of current flow. If you connect these panels in series, there will be no increase in current flow so fusing is not required for this string.

While the fuse/breaker is not required between the panels and CC, having one is convenient for disconnecting the panels from the CC (for maintenance, etc.). I'm thinking of using a breaker in my installation instead of a switch because I think attaching the 10 gauge wire to the breaker would make for a better connection.

Between the CC and battery, a fuse/breaker is necessary to protect the wire between them and it should be placed very close to the battery terminal.

[BradS7535]

Klpauba, thanks for that link, I've been on windynations site but must have missed that page. Looks like I can go with a switch between the panels and CC. I'll probably upgrade the cabling from the CC to the battery to 8 AWG and keep the breaker a 40A since the max output of the controller is 30A .

For the battery to TM, can I replace the 30A fuse with a 30A breaker to get the functionality of a battery cutoff?

[Padgett]

I put in a master disconnect (box from Lowes for an AC) with a 100A CB for the inverter and two 30A CBs one for the solar panels and a second for the coach. Plus a 20A light switch to disconnect the solar.

Master disconnect is for the positive side only, grounding is solid.

8 AWG is rated at 40A. For my 1KW continuous inverter I used #2. (Coffee maker pulls 64A). Can isolate the generator/AC circuit and run the coach 120VAC from the inverter.

Selected the GC2s for three reasons
1) would fit in the rear compartment
2) have maximum power density of any commonly available battery
3) designed for very deep cycling

Know have posted before but not here. Cover & disconnect is removed.

[BradS7535]

Padgett, why did you install a switch AND a breaker? Couldn't you have just flipped the breaker to disconnect the solar?

[klpauba]

For the battery to TM, can I replace the 30A fuse with a 30A breaker to get the functionality of a battery cutoff?

You can, but you need to make sure the electric brakes (and electric jack if you have it) will still work WHEN you forget to close the breaker. You would then need to fuse the brakes and jack separately (with the properly sized fuse).

[Padgett]

Was just thinking I might want to turn the solar including the controller off and leave everything else running. There is also a little float charger connection under the bumper cover and accessible when closed.

[rickst29]

I'm also considering a single 250W panel which will probably only fit on the rear shell. Even if i went with 2x100W panels, with the A/C, TV antenna and vent I'm not sure there is room for the 2 on the front shell.
My 2619 has a shorter front shell than your 2720, and Renogy mono panels have about 19" of flat unused space (front to back) before they would reach the fan mount. (The fan is more "forward" than the AC). I arranged my panels with 3" from the above-stove fan, with about 16" of flat, unused space in front.

But one of my three panels is flex. The lifting weight of 3 traditional panels would be too much more me to handle. (I think that my 2619 was built with skinnier torsion bars than the 2720. They're tuned to maximum already.)

[rickst29]

Can someone explain when a fuse/breaker is needed and where for solar? I'm a bit confused now as to the purpose and if I actually need one between the panel and CC or CC and battery. If I don't need a fuse/breaker I'll just put a switch to disconnect the solar.
I recommend waterproof car breakers for this purpose. When everything is "normal", you don't need them. But anyone who wants to implement with the thinking behind electrical codes and practices for device protection will ALWAYS want to have a breaker between power sources (such as the panels) and their terminating loads (such as the MPPT). In the CC-to-battery case, the Charge Controller is the source - and this wire should also be fused.

I think that the TM 12V system is "like" your car, and the same wiring principals should be used. There are high-amperage fuses from the alternator into the "bus", and the bus feeds a multiplicity of fuses - each no larger than the maximum load which should occur from the "downstream" devices. Depending on the Amperage from your panels, either a 10A, or 15A, or 20A, before reaching the MPPT "Solar In" terminal is suitable. And depending on your MPPT output Amps, or your battery string maximum charge rate, something in the range of 25-30A might be a good choice there.

Here's a good choice for a typical TM battery string: http://www.ebay.com/itm/INLINE-30-AMP-CIRCUIT-BREAKER-MANUAL-RESET-12V-30A-4-6-8-AWG-GAUGE-US-SELLER-/111396780963. I actually use two of them: one from CC into one battery, and the other replacing the problematic TM-supplied fuse from from Batteries to the Load Center. My Panels run less than 10A, but the "Solar +" wire into the MPPT can also run from the TV (at lower Voltage, much higher Amps) so I have that one fused slightly above the TV maximum Amperage - it's another 30A, even though a "pure" solar configuration like mine would call for a smaller Breaker.

Don't trust any electrical wire without protection!

[rickst29]

For the battery to TM, can I replace the 30A fuse with a 30A breaker to get the functionality of a battery cutoff?
Yes - Highly recommended.

[Dchisenh]

Just a heads up on the Renogy flexible panels, they're not being sold by Renogy anymore and there's a voluntary recall on them.

I bought 400 watts worth and installed them last year on the rear shell of my TM and when I went to get my camper ready to go this Spring, I noticed they were dead, basically there's a design flaw in them that leads to a high likelihood of over-heating and shorting when they're mounted directly to a surface. The good thing is that Renogy stood behind them, sent me a box and a return label to ship them back and offered me full refund on my purchase! I used that refund to buy new rigid panels from them and are in the process of installing them now. I think they kinda pushed the envelope with those flexible panels (they're anticipating a redesigned flexible panel relaunch sometime around the Summer of '17), but their customer service was excellent!

If you have those flexible panels, keep an eye on them and remember they have a 5 year warranty from the date of purchase!

-Dan

[Padgett]

Mine are rigids mounted with the Z-brackets so air can circulate underneath. See picture 2 in post 17.

[Dchisenh]

Yep, I saw your install Padgett, very sharp looking! :) How did you mount your z-brackets to the roof; the supplied screws, adhesives, or rivets? I'm thinking about using some blind threaded stud rivets, in case I need to remove a panel. Something along these lines: http://rivetsonline.com/rivet-nuts-and-threaded-inserts/blind-threaded-stud.html

As far as the recall, I was mentioning it for Rick who posted he had one of the flexible ones. :)

-Dan

[Padgett]

Short screws (3/4", the roof is only an inch thick, think #12) squeezing a layer of caulk.

[BradS7535]

I believe the majority of the installs on here use 3M VHB tape to install, that way you avoid putting holes in your roof. This is what I plan on using when I install my system.

[[email protected]]

Just a heads up on the Renogy flexible panels, they're not being sold by Renogy anymore and there's a voluntary recall on them.

I bought 400 watts worth and installed them last year on the rear shell of my TM and when I went to get my camper ready to go this Spring, I noticed they were dead, basically there's a design flaw in them that leads to a high likelihood of over-heating and shorting when they're mounted directly to a surface. The good thing is that Renogy stood behind them, sent me a box and a return label to ship them back and offered me full refund on my purchase! I used that refund to buy new rigid panels from them and are in the process of installing them now. I think they kinda pushed the envelope with those flexible panels (they're anticipating a redesigned flexible panel relaunch sometime around the Summer of '17), but their customer service was excellent!

If you have those flexible panels, keep an eye on them and remember they have a 5 year warranty from the date of purchase!

-Dan

flexible panels made by the same company? I have 200 watts worth and they seem to be doing fine.
Tom

[Padgett]

Cannot speak for elsewhere but in Florida outdoor adhesives alone generally do not last for more than a decade. May have improved some since but learned that the hard way.

[Dchisenh]

Tom, I can't speak to the other companies, but when I was researching those flexible panels when they first came out, the designs looked awfully similar. I remember AM Solar tested them and the first batch they didn't like, then they started selling them with a supposedly thicker outer coating, but they're not selling them anymore. A quick search on Amazon seems like it's new companies selling them now (perhaps they're trying to liquidate old problematic stock?), and if there's a design flaw as Renogy said I'd keep an eye on yours too. All I can say is that mine failed, Renogy stood behind the product and I'm happy with my replacement panels by them.

Padgett, I knew the roof wasn't too thick but I thought it was thicker than that, but good to know! :)

Brad, I agree with Padgett about only using VHB tape. I actually used VHB tape and Geocel caulk adhesive to attach my flexible panels last year and was a bit startled by how easily they came off when I removed them. Yes, getting the first bit loose was hard, but as soon as I did several strong tugs and they started to peel right off. That made me hesitant to rely on VHB alone with these much heavier rigid panels. I think I'm going to try to get my hands on some of those threaded rivet studs I linked to in my previous post because 1) they don't need to go too deep into the roof and 2) if I want/need to remove the panels in the future I should be able to if I use a nut with some loctite on it and maybe a dab of caulk for good measure.

-Dan

[BradS7535]

For those of you who have installed solar, where did you install disconnects (if you did)? Did you install a disconnect between your panels and your charge controller as well as between your charge controller and your battery?

For MPPT at least, they say you shouldn't have your panels connected to your controller without having your controller connected to your battery.

[scrubjaysnest]

We used mc-4 connectors on the roof mounted plus a Midnite Solar breaker between the panels and CC. Same thing for the portable panels. A third breaker was added between the CC output and batteries.
See here for a link to mine and others installs. http://www.trailmanorowners.com/forum/showthread.php?t=16973

[BradS7535]

I'm no electrical engineer, so I'm having trouble finding appropriate switches for between the panels and controller and controller and battery. Ive seen/found similar battery disconnect switches that I've seen you guys used, but was hoping to find a smaller toggle switch or something similar for disconnecting my panels.

The panel Vmp is about 30.1V and Imp is 8.3A. Out of the controller will be the battery charge voltage at no more than 20A.

Are there such toggle switches to handle that power or should I just use the same battery disconnect switches there as well?

[BradS7535]

No response to my switch question above?

Ran into a little problem today. The 250W panel fits on the rear shell when closed, but the rear shell is not very flat, it actually has a pretty significant curvature to it in multiple directions. The center line is the highest point and it slopes down left/right, but it also seems to slope from where the front shell rests to the back front/back. This causes me to not be able to get all 4 (actually 8) z-brackets to sit flush. I checked to see if it would fit on the front shell and it seems to be flatter up there, on the side with the awning. My only concern with placing it there is that the panel is about 40lbs and the front shell already has the awning, A/C, and antenna. Adding another 40lbs to the front shell, especially on the same side as the awning doesn't seem ideal, but there doesn't seem to be a way to get it on the back without using shims under the Z brackets to get it to mount. Any suggestions?

[Padgett]

Dunno, I have two panels with four Z-brackets on each, one on either side of the center.

Are you high centering ? Photo would help.

Nice thing about being on the back is they also shade the bed area.

[BradS7535]

Dunno, I have two panels with four Z-brackets on each, one on either side of the center.

Are you high centering ? Photo would help.

Nice thing about being on the back is they also shade the bed area.

Here is a photo. I didn't take a picture of the back brackets, but according to my memory, the back edge brackets are even further off the shell than the front edge brackets.

Any suggestions as to mounting this flush on the rear shell? There is room for the panel on the front shell on the awning side, and the roof is pretty flat there, but would prefer to put it on the rear shell.

[scrubjaysnest]

I'm no electrical engineer, so I'm having trouble finding appropriate switches for between the panels and controller and controller and battery. Ive seen/found similar battery disconnect switches that I've seen you guys used, but was hoping to find a smaller toggle switch or something similar for disconnecting my panels.

The panel Vmp is about 30.1V and Imp is 8.3A. Out of the controller will be the battery charge voltage at no more than 20A.

Are there such toggle switches to handle that power or should I just use the same battery disconnect switches there as well?
Toggle switches with that current, 20 amp, are hard to find and almost force you into house hold electrical switches.

I used Midnite Solar breakers instead as they are can handle being used as a switch better then standard breakers. They run about $11 each.

As for the panel it needs to be about 1 to 1 1/2 inch above the roof of the for air circulation. When we had our TM, scrubjaysnest solar (http://www.trailmanorowners.com/forum/showthread.php?t=16218) as seen here I made the Z brackets from 1 5/8" aluminum angle.

Other owners install can be found here:Links to owners solar installs (http://www.trailmanorowners.com/forum/showthread.php?t=16973).

A 150 watt panel, 12 v or Vmp of 18 volts is typically a little over 2 feet wide X 6 feet long.

[Padgett]

Am a little confused, that photo is of the back and z-brackets are easy to bend. Also looked from the earlier photo that they could be closer to the front shell, mine have about a 1/2" gap. They are also shielded from the airflow by the front module.

For mine I just used a 20A light switch on the solar.

[BradS7535]

I didn't take a picture of the z brackets that are closer to the front shell but I seem to remember that the outside brackets weren't even touching the shell. I think the curvature of the shell is less at the rear than it is further up where the front shell ends.

[Padgett]

Might need to make some rails with shims to attach it. Maybe move the z brackets to the sides ?

[BradS7535]

I'm going to attempt to install the panel on the rear shell this weekend by sliding the z-brakets around to try to find a place they lay flat on the roof.

One question though, for those of you who used the VHB tape, did you remove the Krystal-Kote or just clean the area with IPA?

[BrucePerens]

If I am reading the data-sheet (https://multimedia.3m.com/mws/media/67100O/3mtm-vhb-tapes.pdf) correctly, both aluminum and polyester (Krystal Kote) have high surface energy and the tape will bind to them. Aluminum is about 10 times higher than polyester, though. Also read the surface preparation document (http://solutions.3m.com/3MContentRetrievalAPI/BlobServlet?locale=en_IN&lmd=1257400213000&assetId=1180621425284&assetType=MMM_Image&blobAttribute=ImageFile). They want 4 square inches of VHB per pound supported to deal with the issue of surface creep. According to the MSDS (http://multimedia.3m.com/mws/mediawebserver?mwsId=SSSSSuUn_zu8l00x4Y_GP8tS5v70k 17zHvu9lxtD7SSSSSS--)3M adhesion promoter is 90-95% isopropyl alcohol and less than one percent a trade-secret chemical (which isn't guaranteed to actually do anything).

[rickst29]

I've never had an "issue" with my VHB-taped brackets, sti=uck directly on to clean TM paint.

[flipflop]

Alright, I have the Factory Data Sheet for this '08 2619 I bought, shows all the factory installed equipment.

The data sheet shows factory solar is a "Matrix PW-85" and a "Mark 1512" charge controller.

Here's the link to the Matrix PW-85 http://www.pvsolar.com/matrix/pw85.html

Here's the link to the Specialty Concepts Mark 15 charge contoller http://specialtyconcepts.com/SPECIALTY_CONCEPTS_PDF_FILES/MARK_15_SPEC_SHEET.PDF

QUESTION: Is the solar charge controller integrated into the shore power AC system? Or do they operate independently?

[rickst29]

The Solar Controller is DC-Only, so it only interacts with the Power Converter's converter section (Not the 120VAC input, or the 120VAC outlets).

When you're plugged in and it's sunny: The Power Converter will "see" that the 12V battery system is already at high voltage, and it won't attempt to charge it at all. But at night, the Solar Charger won't create any Voltage or Current - and the Power Converter, if plugged into 120VAC, will "see" that (at least) some trickle charge is necessary. If 12V loads pull down the Voltage some more, the the power converter will provide more.

So just leave them both plugged in at the same time. In the morning, Solar system checks for an opportunity to start charging more often - and once the Converter pauses for measurement, the Solar will almost immediately start up and prevent the Converter from restarting (unless power consumption exceeds the Solar Controller output.)

[flipflop]

The Solar Controller is DC-Only, so it only interacts with the Power Converter's converter section (Not the 120VAC input, or the 120VAC outlets).

When you're plugged in and it's sunny: The Power Converter will "see" that the 12V battery system is already at high voltage, and it won't attempt to charge it at all. But at night, the Solar Charger won't create any Voltage or Current - and the Power Converter, if plugged into 120VAC, will "see" that (at least) some trickle charge is necessary. If 12V loads pull down the Voltage some more, the the power converter will provide more.

So just leave them both plugged in at the same time. In the morning, Solar system checks for an opportunity to start charging more often - and once the Converter pauses for measurement, the Solar will almost immediately start up and prevent the Converter from restarting (unless power consumption exceeds the Solar Controller output.)

Thanks, good info, seems like a good setup.

[BrucePerens]

The solar and converter chargers are in parallel. I have been running the Morningstar TS-MPPT-60 and a Parallax Boondocker in parallel, and watching with a Blue Seas 1830 monitor, it doesn't seem to be a problem.

[BradS7535]

Forgot to post a link (http://www.trailmanorowners.com/forum/showthread.php?t=17711) to my completed install. Single 250W panel on rear shell with MPPT charge controller. Perhaps the link could be added to the sticky thread of solar installs.