Newbie installing small system in truck camper

Geronamo98 · March 2010

First, I want to hand it to you all for putting together a top notch forum, Nice Job!

Second, I have read through a lot of posts and I think I have my system designed and sized correctly for my application, so...

Third, Please let me know if you can offer any suggestions on improvements, things I missed or miscalculated, or tips for mounting to camper roof. I am listening to what I have learned on here and asking before I order. Thanks!!

I have calculated that I use ~50AH per day, and using multiple calculators I found I would need more than 160watts of solar, I currently have an AC charger and a 110AH battery that came with the camper.

I am ordering:
Morning star Sunsaver 15amp MPPT charge controller
remote display meter for said controller
temp sensor for said controller
Two Kyocera KC85TS PV modules that will be wired in series

I will be using ~15 feet of 10AWG wire from panels to controller.

Thoughts?

Thanks again for all your help!!

Cariboocoot · March 2010

Re: Newbie installing small system in truck camper

At 50 Amp/hrs per day you may be disappointed with a 110 Amp/hr battery. That's just about 50% capacity each day: what is considered the maximum limit.

Assuming this is a 12 Volt system? You might also be disappointed with 165 Watts of panel, as one of the problems with campers is getting the panel pointed at the optimum angle. This makes a drastic difference in output. Are you going with a fixed mount or will it be just set up on the ground when camping? With the latter you could get the orientation much closer to optimal.

You probably won't see any benefit from the MPPT controller on a small system like this. My advice would be to save your money there and go for more panel/battery with a PWM controller. A remote temp sensor is always a good idea.

50 Amp/hrs per day isn't a lot: 600 Watt/hrs. You've already discarded the electric kettle, eh?

BB. · March 2010

Re: Newbie installing small system in truck camper

You might also look at panels over 100 watts--there can be significant price savings (if you have the room to mount them):

Kyocera KD135GX-LPU 135 Watt 12 Volt Solar Electric Panel
Weekly Special - Kyocera 135 Watt 12 Volt, with MC4 cable connections
$362.85, 2 for $720.00, 8 for $2,800.00

Kyocera Solar KC85TS 12 Volt 85 Watt Solar Panel
KC85TS panel 87 Watt 12 Volt
Our Discounted Price: $397.00

Get a 50% larger panel for $35 less... (I am not with NAWS--just cut and paste from their webstore).

IF you can mount the panels so they can tilt/aim at the sun (especially winter)--can be a big help.

Some folks make the panels movable--park in the shade, put the panels in the sun (make sure they are secure--one gust of wind an you have $800 of modern art).

I like battery monitors (Amp*Hour / Watt*Hour meters)--can make battery management a lot easier. Might be a bit expensive to justify for a small battery bank--but still a nice to have item to help prevent deficit charging (taking more energy from the battery than you are recharging back in).

Will you have a backup generator/power source + battery charger? Long term camping or just weekend trips (charging on utility when at home)?

-Bill

Geronamo98 · March 2010

Re: Newbie installing small system in truck camper

Thanks for all your ideas and thoughts!

I have been fairly happy with my battery(12v) so far but I am planning on buying another in the future. This is a small pop-up truck camper that has very few amenities. There just isn't much in there to use. That said, I over estimated my use by ~20% when I came up with that 50AH calculation. I thought a lot about getting two larger panels (clearly cheaper and will have more raw watts, nearly 270 if I get 2-135's), but from what I read on a lot of these posts, it sounds like it is more efficient to go with two smaller panels and the MPPT. I would be happy to get two larger panels and the PWM controller. Clear money savings, but would that suit my needs well if I am out in winter or in a slightly shaded campsite?

I do believe I have the real-estate available for two large panels and don't plan on making the panels tilt-able.

I like battery monitors as well, anything that helps me measure how much I am using my investment, is a good investment.

I plan to boon-dock for 5 days at the most, then go to campsite (with power) or home. I only have 3 days of water storage so that limits me anyway.

No generator, I was going to buy one, then started to price the solar as an alternative way to spend the money.

These are some really helpful thoughts and feedback guys, thanks a ton!

BB. · March 2010

Re: Newbie installing small system in truck camper

MPPT controllers are nice--but realistically with the correct panels and configutations, you are probably looking at an average of 10-15% additional power collected on cooler days over a PWM controller.

You can use the PV Watts program to compare mounting options at different locations--Obviously, your best improvements will come from tilt mounts the farther north you are during winter.

A small Honda eu1000i genset would be handy (quiet/efficient) for those times when you have a run of cloudy weather--Lead Acid batteries do not want to spend long periods of time below 75% state of charge (days/weeks/months). But you can only pack so much in a small camper.

-Bill

Geronamo98 · March 2010

Re: Newbie installing small system in truck camper

Thanks BB,

do you have any suggestions for PWM controllers? With 2-135w panels, I would wire those in parallel right?

Those stand-alone battery monitors are pretty expensive, do the charge controllers do any of that as well?

Thanks

BB. · March 2010

Re: Newbie installing small system in truck camper

Our host has lots of controllers that they stand behind... Morning Star, Xantrex, and others are probably all fine--If you have the choice, pick one with a remote battery temperature sensor option. It will help charge the batteries a bit faster and a bit more full (hot batteries require lower charging voltage, colder batteries require higher voltages... Charge controllers tend to be high at guessing battery bank temperature--controller heats itself up while working).

You would parallel your two solar panels when charging a 12 volt battery bank (ideal is around Vmp=17-18 volts and normal charging around 14.4 volts). The difference between Vmp and Vbatt allows for hot panels (Vmp drops when panel are hot) and for a bit of wiring drop.

Yea--Battery Monitors are not cheap... If they save you one battery bank--they almost pay for themselves.

If you are looking at a small system--Something like one of these may be an alternative for $60 or so--Used by RC guys to measure their battery pack performance. They do not "reset" to 100% full like a battery monitor when it detects a battery is fully charged--you would have to hook up a extra switch that would allow you to "zero out" the meter when you think the battery has been fully charged.

A few companies offer Battery Monitors with their charge controllers (options or part of package)--but these are for much larger models (60 amp or larger).

Many smaller charge controllers offer their own charging data history (sometimes through on-board/optional displays; or through optional computer interfaces)--but they only "know" about the current that they output--not how much power has been taken/added to the battery bank (important so that you don't kill your batteries).

You can (and should) use a volt meter to measure resting voltage and a hydrometer to measure electrolyte specific gravity. Read a couple battery FAQ's to get a better idea of what you are up against trying to keep a battery happy.

Deep Cycle Battery FAQ
www.batteryfaq.org

-Bill

Geronamo98 · March 2010

Re: Newbie installing small system in truck camper

OK, I think I have changed my design and saved some money, thanks for the help!

2 kyocera 135W panels
1 MS dual battery charger
temp sensor for said charger

Debating getting the xantrex linklite battery meter.

Those panels use the MC type connector, do I have to order a special cable to run to my charge controller or will I be able to just wire them in. The MC connector confused me.

Thanks

BB. · March 2010

Re: Newbie installing small system in truck camper

As I understand, if you cut off the MCx connectors--the vendor has the right to void the warranty.

The simple way around it is to purchase a couple $20, 3 foot, Male/Female MC4 jumper cables and cut them in 1/2 to wire into your harness/boxes (there is also a tool used to unlock the "locking" MC4 connectors--more baby proofing by the NEC). (PS: I linked to the pre-cabled Kyocera panels--but there is still a junction box version available--but the panels cost $60 more per panel).

You are very welcome for the help--And please let us know how everything works out in the end--And you can answer the next RV questions as an expert!

-Bill

notsobright · March 2010

Re: Newbie installing small system in truck camper

Geronamo98 wrote: »

OK, I think I have changed my design and saved some money, thanks for the help!

2 kyocera 135W panels
1 MS dual battery charger
temp sensor for said charger

Debating getting the xantrex linklite battery meter.

Those panels use the MC type connector, do I have to order a special cable to run to my charge controller or will I be able to just wire them in. The MC connector confused me.

Thanks

sound like a nice set-up! I have the same controller

I think if this is the one you are considering:

http://store.solar-electric.com/modubachco25.html

Im not aware of any other for dual batteries but this one is 25a

I was considering the linklite for monitoring until I read this thread here http://forum.solar-electric.com/showthread.php?t=7259

I am waiting on more info before I purchase a monitor but I will tell you that I have noticed some voltage spikes above 15v with the SSD according to the MS meter. I have talked to their tech supports about it and they said its normal and only spikes and not substained so no worry.

I was under the impression their included meter would also monitor and it does do simple monitoring (indicating this spike) but now that I know it cant relay the durration Im looking at better monitors.

having know this ahead of time I might have skipped the SSD package with the remote meter included abd just bought the SSD Controller.

If you decide on the SSD for sure I think you will find that our forum host NAWS has beyond question the best price for this unit anywhere! I not just saying that, you can get the unit with the meter here for less than anyone else sells just the controller for. and literrally half of what others are charging for the same package.

I didnt find anyone else that even came close to NAWS on the MS SSD w/meter. Ive also found they have the best prices on the Kyocera panels aswell but not as substantially less as with the SSD. still considerably less.

the SSD IMHO has room for improvement but there isnt another controller available that does what it does so Im satisfied with it. I will be working with them and inputing my observations and experience on the SSD to hopefully advance the unit with improved firmware. other issues Ive had were if you want to use the PC to alter programming you must first connect PC then remove all power inputs from the controller for the software to recognize the controller then reinstall PV and battery input.

I found this out the hardway and hard to go back and rewire my set-up with inline switchs to accomodate this.

this is one of the issues I hope can be worked out with new firmware.

yes, keep us posted on your system! allways good to have more input in the RV area and specifcally with the SSD controller.

Geronamo98 · June 2010

Re: Newbie installing small system in truck camper

Update on truck camper solar installation...

The install went flawlessly!! Connecting everything together was quite simple (although I am somewhat electronics oriented). The instructions that came with everything were very clear.

I am very happy/impressed with the amount of current I have been seeing out of this setup. On an overcast day I can get 5 amps easily. On very clear/sunny days, I have reached 16 amps. This was enough to run my refridgerator on DC for 4-5 hrs when I ran out of propane one sunny day. It was really nice not having to hurry to go get more propane.

The xantrex meter was a great suggestion. It was kind of expensive but now I really know where my batter charge is all the time. I wish the instructions that came with it were a little more clear though. Sometimes I will use 15AHs in a night and the next day, I watch it start to charge and it never gets back to full. The only time I can get it to show a full charge is when I plug it in at home. The solar will bring it within 1% of full but never full. I have a lot more reading to do to understand that, but I am very happy with the whole setup.

If I could suggest anything to someone making this investment it would be to buy more panel then you think you are going to need. I did this and it has worked out well. I hear many people on here discuss their needs, purchase, then come back saying they need to get more. I calculated my needs for a night (a very wasteful night), doubled it, then calculated how much solar I would need to refill that need in a day, then doubled that. Roughly speaking.

Thanks to everyone on here for their help!!

Geronamo

notsobright · June 2010

Re: Newbie installing small system in truck camper

thats great G! its a good feeling when you get a new system set-up and running.

the SSD controllers factory setting may not be a good match for your battery specs and that could be a reason you cant get 100% but you have to get the modbus adaptor and software to alter it.

I need to clarify some things:

notsobright wrote: »

I have noticed some voltage spikes above 15v with the SSD according to the MS meter. I have talked to their tech supports about it and they said its normal and only spikes and not substained so no worry.

notsobright wrote: »

other issues Ive had were if you want to use the PC to alter programming you must first connect PC then remove all power inputs from the controller for the software to recognize the controller then reinstall PV and battery input.

I had missed the max output setting earlier. Ive since reprogrammed it and havnt had anymore spikes.

I also downloaded the latest software which now includes a logging feature. since then I can connect and read the controller without having to turn everything off first so thats not an issue but at the same time I used a new laptop too so I dont know if that problem was my old laptop or the MS software but Im thinking it was probably my old laptop.

good luck with the system!

icarus · June 2010

Re: Newbie installing small system in truck camper

~$200 spent for a battery monitor will save money in the long run, but it also adds considerable "entertainment" value to your system. There is something about watching the AHs roll in (and out).

The Rogue 3024 MPPT controller @~$300 will also provide many of the functions of the Tri-metric, with the added benefit of a controller. A great controller, but way to big for your use, and physically it is fairly large. I think the Morningstar MPPT controller may also have nice battery monitoring on board as well.

Tony

Newbie installing small system in truck camper

Comments

Categories