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FYI Solar 101 - A General Guide to Solar in your RV or Motorhome

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Silly question, but I see people with pirtable panels at RV parks, they move around on the ground to face the sun. Can I just get one, with battery connections and hook to house battery to charge the battery? I obviously know nothing about it, but we can hook a battery charger to it and charge it like that.
 
My question is how long does install take? what is the average install time for pros? for random owners?

Second, my thought was dividing it into two processes:
1. install inverter and extra battery to use with portable solar panel
2. install roof panels and more batteries
Does that sound reasonable?
My thought was that I want to be able to take out the RV for a weekend and use some solar for extra power. If all goes well and we enjoy this a lot then maybe install more so we can do longer trips without plugging in. This would be to save costs (as well as reduce weight short term since more panels and batteries add weight).

Our RV is a Minnie Winnie 22R with an Onan generator 4000. It is NOT 'solar ready.' We live in the SW where it can get VERY hot in Summer. Even at night. We try to escape the heat by traveling in Summer, but there will be times where we just need to run that a/c for a whole day or weekend, maybe longer.

Silly question, but I see people with pirtable panels at RV parks, they move around on the ground to face the sun. Can I just get one, with battery connections and hook to house battery to charge the battery? I obviously know nothing about it, but we can hook a battery charger to it and charge it like that.

I'm no expert and haven't done anything with solar but I've been reading. From what I've read, those people have RVs that have 'solar prep' and so they can just plug those portable solar panels into their RV to add some power. It's not as much power as a roof full of panels though and can obviously only generate power when parked and the panel is set up (not on the road or in storage).
 
How long does it take? Depends on what is being done. For me which was initially 8 panels on the roof, done by myself. 1 day (a RV day is a few hours of course, not 8-10 typically) was the basement work installing the solar controller and wiring to the battery. Essentially built it on a board on the picnic table then mounted the board and connected the wires. Next step was placing and securing the panels. Final step was the wiring. Then back for cleanup including tie downs, dicor around the solar panel mounts to keep moisture and yuck out of the adhesive area. I'd say 3 "RV" days minimum if you break it into the phases. More or less based on the level of the job such as replacing batteries, inverter, etc. In the end, give it a week whether self or professionally.
 
Thanks for the writeup and the offer to answer questions. Here are my initial questions:

While I think I’m competent enough to do the install myself, I’m interested in taking the coach somewhere and just having it done in a day or so. I reached out to AM Solar, but given that they are on the West Coast and we haven’t made it out that way yet due to having other commitments that limits the time we have to travel that far at our slow pace, I’m wondering if you’ve found any competent RV Solar companies in Virginia or surrounding states?

Newmar’s solar prep includes a blue cable with RJ45 connectors that goes from the basement to the cabinet above the driver. Did this cable get used?

Related to the above question, does the MPPT have a remote monitoring capability that would be installed inside the coach?

I noticed that the MPPT has a LED indicting which charging mode (ie. bulk, absorb, float) it is in. Does the MPPT get this info from the inverter/charger so that it can adjust the output voltage accordingly?

Is there such a thing as installing too much solar capability? It would seem that it would be cheapest to install the most panels at the time that the initial installation was being done. Is there a downside?
 
Silly question, but I see people with pirtable panels at RV parks, they move around on the ground to face the sun. Can I just get one, with battery connections and hook to house battery to charge the battery? I obviously know nothing about it, but we can hook a battery charger to it and charge it like that.
Hi @Woodsie8* Some things you should know. There are only two types of solar panels. Those that are bolted down and broken ones. The difference is one gust of wind. Second thing you should know. Solar controllers save batteries and should be considered a necessary part of the package. two types are available PWM(not great) and MPPT controllers. MPPT stands for maximum Power Point Tracking. The idea is panels produce their highest power level at only one point on the output scale and the controller is designed to find and maintain that point. Don't think that a charge controller need break the bank. My charge controllers are MPPT controllers the last one a 60 amp controller from Amazon cost me 100 dollars with shipping. I use a different controller for panels (individually or strings) because different angles or shading will bring down that string. I am inclined to use flexible panels where I can for weight reasons. But for my setup I need the frame so use house panels (250 watt 60 cell panels). If you want to run the panels in series have fun. When voltages are more than 2.5 times the battery voltage, efficiency of the controller goes down. can't get around it, it is the nature of the buck converter. (DC to DC converter) question this, look up buck converter data and design data for them. A point here. with only small losses in output you can use a buck converter as a solar controller, I know I have done it. They work better when lithium is used and the voltage drops to low they will self start because they never shut down. You only need enough batteries to get through the night, or if you have the space 4 days of cloud cover. That depends on your usage, and enough solar to supply power enough to keep up with demand and trickle charge the bank. You can never have to much solar, I repeat what I hear like a record. I happen to believe it though, would like to aquire another 500watts because I can make them fit on the roof, already have 1000 watts, and a 280 watt panel I see no way of putting on the roof.
Another point: this is important. MPPT controllers choose what voltage to run at with the battery bank hooked up. This means the battery should be the first thing connected and the last thing disconnected. They have been known to self destruct when this order is not used. For solid connections air gap breakers should be used for both battery connections and solar panel connections.
 
Ih my gosh! Thanks for the info! I have a 20’ rig, not a lot of room up there. The roof is difficult to clean, as it is. I could out hinges in frame to lift. I live in the forest and I just know a branch or heavy limb will land in it. Thoughts?
 
My 26ft fifth has a 20ft box the rest over the hitch. I have 1000w over the box only. I look for spots in the forest that are clear of trees. I don't park under the shade of trees, what is the point if solar is the game.
 
Thanks for the writeup and the offer to answer questions. Here are my initial questions:

While I think I’m competent enough to do the install myself, I’m interested in taking the coach somewhere and just having it done in a day or so. I reached out to AM Solar, but given that they are on the West Coast and we haven’t made it out that way yet due to having other commitments that limits the time we have to travel that far at our slow pace, I’m wondering if you’ve found any competent RV Solar companies in Virginia or surrounding states?

Newmar’s solar prep includes a blue cable with RJ45 connectors that goes from the basement to the cabinet above the driver. Did this cable get used?

Related to the above question, does the MPPT have a remote monitoring capability that would be installed inside the coach?

I noticed that the MPPT has a LED indicting which charging mode (ie. bulk, absorb, float) it is in. Does the MPPT get this info from the inverter/charger so that it can adjust the output voltage accordingly?

Is there such a thing as installing too much solar capability? It would seem that it would be cheapest to install the most panels at the time that the initial installation was being done. Is there a downside?

Let’s start last question first. Not really. A solar panel, when exposed to sunlight is like having a battery. More solar panels equals more batteries. Aside from cost and weight...there is no downside to having MORE. You aren’t likely to fit so many on an RV that you will hear anyone say...”I think I have too much.” Never heard anyone say that, yet.

The solar charge controller is Independent of the Inverter/Charger. Well...if you have a Magnum MS inverter and add a Magnum PT-100...they do talk to a common remote...and share settings. But think of the Solar MPPT controller as an independent thinking device. It looks at battery voltage and charges accordingly. If there is something already charging, when the controller wakes up at daybreak...it may idle in Float mode...and let the other charger go at it. If it wakes to less voltage...it will go thru BULK, ABSORB, and FLOAT, which may cause the other charger to idle in FLOAT, Standby, Silent, etc...as it’s programming is set. If you apply a large load...and both chargers see a dip in voltage...they may both hit the party by going back to BULK at the same time. You really don’t have to worry about it too much. It all happens automatically, once set for the correct charge parameters.

Some inexpensive controllers are stand alone. And you have to see the settings/readings on the unit. Others have a remote panel display. The option many take is the Victron SmartSolar series. It has built-in Bluetooth... You download the free Victron Connect app for your device...pair the two...and now you have a very intuitive display. You set, control, monitor, and even update firmware....all from your phone or tablet. I don’t want to put the cart too far ahead of the horse...but Victron devices can also be linked a few different ways. VE.direct is a proprietary cable. If you connect your Solar Controller to a GX device by VE.direct cable...such as Venus GX or Cerbo GX...and you have the GX connected wirelessly/or wired to an internet router/hub. You now have the ability to monitor and manage your solar from anywhere in the world, it is called VRM or Victron Remote Management. If you have your rig stored somewhere else...it sure is nice to be able to check in. It can also be set to give you email alerts to any condition you care to be alerted to. I monitor mine mainly from the VRM portal...and have an iPAD mini mounted to my A-pillar and can see the display while driving. More for fun...or running high loads like an AC unit.

You can add a remote to the cabinet with the solar option RJ cord...but if you go with Victron SmartSolar...it’s kinda a big step backward. The Victron app is easier to read, interpret, and control. A remote display means you have to stand and bend your neck. Reach up. Cycle thru multiple tiny display pages...and toggle up/down repeatedly to adjust settings. After using Victron Connect...the remote will feel like the stone ages.

I understand that having someone else do it adds convenience. If you have all the parts and tools...good weather...and assistant...you can knock the job out in two days. One day on the roof...mounting panels, running wires, adding combiner box, and connecting to the solar prep.
The other day is spent in the basement...mounting switches, breakers, controller, wires, fuse...and battery terminations. Actually, doing the basement first is better...because you will not Have to worry about loose ends when you start applying solar PV energy. It isn’t a difficult task. There are positive and negative wires...you’ll have to cut, strip, and crimp terminations on wires...apply colored heat shrink for a neat job. From the mounts (I used AMSolar) to the wire terminations...there are step by step video instructions on AMSolars website or YouTube. Beside saving yourself a lot of labor expense...having a first hand knowledge of your system will pay dividends. Instead of having a system plopped into your lap...you’ll have most likely read and reread the manuals before and during installation. When done...you actually know what the readings are telling you. If something isn’t up to par...you know where stuff is and where to look for connections, components. There will be no mystery. I‘m not recommending anyone get up on the roof, if it isn’t something they feel safe doing. You have to be careful. It can expose you to a fall hazard. So, please don’t bite off more than you are comfortable with...just because I promote self-installation. Only you know if this falls within your personal comfort zone.

Most of us joke...after installing the system ourselves we say...”Now I know why it’s so expensive to have one installed”. You’ll get a workout...no doubt. But, it is a rewarding experience and really gives you a detailed insight into the working of your system.

Sorry for being long winded. Ask questions...we all did...as the first thing you build is the system in your mind. After you get it built completely in your mind...you will be able to build the physical system on your coach.
 
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BTW...the “Victron Connect” App is free...and you can launch it in simulation mode. Select the type of solar controller you would like to view and you can become familiar with the settings and options without even purchasing a charge controller. All of the Victron manuals are available free online as well. I reviewed the manuals for both of the charge controllers I was considering before purchasing. The Manual for the Magnum PT-100 has some excellent worksheets for determining amp rating for breakers and wiring. I recommend downloading it even if you do not purchase a PT-100 solar charge controller.

The Victron controller I have is the Victron SmartSolar MPPT150/100-TR... As the name implies...it can handle 150v PV input...and it will output up to 100A of charge.
 
Charlie - Thanks for the detailed response. It really helps in understanding the capability, especially the part about the MPPT being a charger and the coach’s two chargers (MPPT and Xantrex SW3012) working in parallel. I hadn’t thought of it that way.

I previously purchased a BMV-712, but haven’t yet installed it. I had looked at connecting it to my SmartHome capability via a VE.Direct RS232 cable so that I can remotely monitor its data in addition to all the stuff available on the RV-C network. I’ll probably continue to look into this and include the MPPT as well. I prefer having control of my own data/system instead of relying on a cloud service, but will utilize a cloud service when it’s best to do so.

As I get older, getting on roofs is not something I look forward to. Especially the transition from the ladder to roof and vice versa. I just remembered that my brother recently purchased on of those scissor jack lifts like they have at the Newmar Service Center. That would definitely make the install more comfortable, thus perhaps I can do the install myself.

I understand that the solar prep includes two 6 AWG (?) wires to take the solar panel power to the basement installed MPPT. I understand that there is a limit as to how many amps can flow over the wire and the solution to providing more solar power watts to the MPPT is to increase the voltage begin carried over the wire either by using higher voltage panels or by connecting several panels in series (similar to how the coach’s 6V batteries are wired). Do I understand this correctly? Is there an ideal voltage? I assume the limitation will be based on the MPPT input voltage capabilities?

Thanks
 

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