Whats the best Solar Charge Controller?

[Keyair]

In the planning stage of a Solar Charging System.
Its gonna be a pretty big system for dry camping/boondocking.
I am working back to front, so have decided and sized my batteries, and now I need to figure out what the best Solar charge controller?
Searched, here and on the internet, and am a little confused...

[lewster]

'best' is a relative term.

If you have sized your battery bank and decided on the panels that you intend to use, I would suggest a look at Welcome to AM Solar - Your RV Solar Specialists since 1987.

They are RV solar specialists and have some great products.

(of course, I'm not biased or anything, but the system that I have on my service van has done it's job and functioned flawlessly for over 3 years now.)

[Wabbiteer]

Its gonna be a pretty big system for dry camping/boondocking.

You do have a lot of real estate on the roof of a 34' to play around on.

Can you better define the PV wattage?

[tfmkevin]

Hi,

For what it's worth, I'm an electrical engineer, I researched this quite a lot (I'm geeky that way) and I just had a MPPT controller from AM Solar installed (along with their panels and 6 Lifeline 6V AGM golf cart batteries.)

I'm thrilled with the performance so far. Regardless of the supplier, I'd get an MPPT controller instead of a PWM controller. You get significantly more charge current from your panels that way. I'd also only consider AGM batteries. Their increased charging efficiency makes up for a lot of panel area as well.

The only thing that you can't change is the amount of available space on your roof. Even on a unit the size of yours, there's an amazing amount of stuff up there blocking potential panel locations. We ended up filling just about every available spot on an International 27FB, and we had room for 3 "100W" panels plus 2 "50W" panels. The wattage ratings are in quotes because best case you will never get that kind of wattage from them to the batteries. With our "400W" of panels, we've gotten as much as 30 amps to the batteries (on a sunny day in the Pacific NW). 30A at 12V would be 360W. That (to me) is amazing performance from the panel/controller combo.

We had our system installed at AM Solar, and the folks there seemed to be amazingly competent and extremely friendly and helpful.

[thecatsandi]

Originally Posted by Keyair

In the planning stage of a Solar Charging System.
Its gonna be a pretty big system for dry camping/boondocking.
I am working back to front, so have decided and sized my batteries, and now I need to figure out what the best Solar charge controller?
Searched, here and on the internet, and am a little confused...

Morningstar Corporation » TriStar MPPT

[Gene]

There's a lot of useful information on this thread: http://www.airforums.com/forums/f448...ort-62608.html

Gene

[MaxAB]

Originally Posted by CrawfordGene

There's a lot of useful information on this thread: http://www.airforums.com/forums/f448...ort-62608.html

Gene

I designed my solar package around my needs. We wanted more electrical power storage, so we went with an array of four deep cycle AGM 6vDC batteries - loads of available amp-hours.

Next, I selected a 200-watt dual facial Sanyo panel. I didn't want a tilting-type mount, this panel is flat (horizontally) mounted aft of the AC unit. I've polished my exterior and thereby get a bit more PV activity from the reflected light underneath the Sanyo. Its a higher voltage output - nominally 60volts depending upon conditions.

Since its a higher voltage output, I chose the MorningStar MPPT charge controller with the optional remote digital read-out.

I've had it operational since last October and have yet to break out the Honda EU-2000 from the back of the Suburban! We've had our rig out for over 30 days since October with not a problem.

I've attached some representative photos, FYI... The outside shot will show the Sanyo panel mount location, the interior shots are before/after pictures of where I mounted the charge controller and digital read-out (look to the right of the icebox bulkhead near the window)...

To augment the electrical system, I designed in a Go-Power 2500-watt inverter with a remote on/off switch. This allows us to energize the AC circuits (micro/convection oven, appliances, wife's hair dryer, etc.) without using the generator.

Glad to help you out with any questions you may have....

Keep it GREEN - nothing like solar!

[RickDavis]

I am using a Specialty Concepts Inc. 20 amp Mark PV Controller.
It has been in service for 7 years as have my Sam's Club golf cart batteries.
I chose this controller because it turns on and off based on voltage at fairly regular intervals and is adjustable.
I purposely avoided something with pulse width modulation or anything that switched super fast for fear of noise in my Ham Radio gear. This may not have been a valid concern. I was just being cautious.
With 250 watts of panels we rarely use a generator, usually in the National forests in FL during the winter where we are dealing with short days and trees. I don't recall ever using the generator in the summer. WE go for months with no hookups and it has worked out well.

[Keyair]

This is my plan so far...
Move the coach battery to the front of the slide out compartment, and by removing the "tool box" partition, I could get 6 x 6v golf batteries in there with it... failing that I will just mod a slide out drawer on the other side... or maybe do that as well, and have 8 or 10 batteries.
I think the drawer is too shallow for the taller batteries, but as the bottom of my drawer is already corroded, and has a few holes, and I plan to replace the steelwork, so will just make a drop floor there.

I do have a lot of spare space on the roof, and most of my use for the M/H will be in the south west, I think I will have enough for my needs.
Thinking about adding a 12v water heater element for the overload electricity.
I have almost 1 KW of 6x6 tabbed cells sitting in my garage, that will be split between my Airstream and my other Dodge Van project, so I will be making some custom frames, and matching the space I have.
The think I am trying to figure out is if I have, say 300w of output, do I have to have a Controller that can handle that?
I am still learn

[RickDavis]

Your controller should be sized to handle the max output of your panels. preferably with a little room to spare in case you want to expand later.
Most panels put out around 18 volts so your 300 watts would be a charge rate of around 17 amps which would make a 20 amp controller the bare minimum. You won't always see that high a charge rate but you need to be able to handle it..
I have occasionally seen 14 amps or more from my 250 watt system when things are just right.

[ostream]

Originally Posted by tfmkevin

Hi,

For what it's worth, I'm an electrical engineer, I researched this quite a lot (I'm geeky that way) and I just had a MPPT controller from AM Solar installed (along with their panels and 6 Lifeline 6V AGM golf cart batteries.)

I'm thrilled with the performance so far. Regardless of the supplier, I'd get an MPPT controller instead of a PWM controller. You get significantly more charge current from your panels that way. I'd also only consider AGM batteries. Their increased charging efficiency makes up for a lot of panel area as well.

The only thing that you can't change is the amount of available space on your roof. Even on a unit the size of yours, there's an amazing amount of stuff up there blocking potential panel locations. We ended up filling just about every available spot on an International 27FB, and we had room for 3 "100W" panels plus 2 "50W" panels. The wattage ratings are in quotes because best case you will never get that kind of wattage from them to the batteries. With our "400W" of panels, we've gotten as much as 30 amps to the batteries (on a sunny day in the Pacific NW). 30A at 12V would be 360W. That (to me) is amazing performance from the panel/controller combo.

We had our system installed at AM Solar, and the folks there seemed to be amazingly competent and extremely friendly and helpful.

What are you using to monitor battery state/energy usage? Did you also add an inverter? Was there anything required to support the 550lbs of batteries? Thanks

[bonginator]

For those of you with the MPPT controller share the basics of your configuration and what the total cost was with installation? Wemprobably would be targeting 200 watts and I would like to get a sense of cost for the investment.

Thanks...

[Wabbiteer]

The charger is the heart of the system and one appliance you shouldn't want to buy twice - you need a clear map of what your Safari's roof will accept in panels - and what voltage/amperage you want to run at.

Its a misstep to think just in panel watts - the cost of the MPPT controller would probably buy an extra panel and just about make-up for any missed power the MPPT would have produced.

Anyhow, its a relationship between your battery discharge & amps required to replace them, if you use 100 amps over a period of time then count on needing 120 amps over some period of time to replace them. The overage there goes toward wire losses, charger losses, and the battery electro-chemical losses.

It's a tangled web to wade through, but to run a higher voltage off the roof into an MPPT controller keeps losses lower, and buying a somewhat oversized controller will allow more panels in the future as an easy upgrade.

I went with a self-installed system - two 123w Sharp panels bought surplus (now selling for <2/3rds what I paid) and two 50-watt Sun Electric panels bought new, and an eBay Outback MX-60 sixty Amp MPPT charger nabbed for $300 shipped - so less than $1000 without the batteries or installation...

[lewster]

I would HIGHLY suggest AM Solar as they are the only direct source of solar charging systems that are specifically designed for RV use. They have been the OEM supplier to the large motor home manufacturers like Monaco, Country Coach, Beaver, Safari, Holiday Rambler and many others for many years. Surely no flash in the pan or one that has just recently jumped in on the solar chic.

The most important factor to consider, especially if you are the DIY type, is that there are always qualified and friendly folks at AM Solar to answer your tech support and installation questions.

Sure, you might get a cobbled together system for less money on the web, but with their new hotter panels running at around 18% efficiency, their much smaller footprint for the 100 watt panel seems like it was custom designed for use on an Airstream. Their specially designed MPPT controllers from Morningstar have capacities up to 60 amps and do a superb job of using the hotter voltages from the panels to boost the useable charging amperage seen at the batteries.

Check out their web site at Welcome to AM Solar - Your RV Solar Specialists since 1987 and see for yourself.

[PaulAir]

I'd recommend BlueSky Energy
Blue Sky Energy Inc. | Our Products

Sounds like the 2512i would be a good match. I've used them since their first MPPT controller came out. There is a remote monitor available as well.

[Dwight]

I would recommend the Morningstar Tristar TS-MPPT-45.....I have used the Blue Sky unit and wasn't happy with the performance or quality.....

[PaulAir]

Originally Posted by Dwight

I would recommend the Morningstar Tristar TS-MPPT-45.....I have used the Blue Sky unit and wasn't happy with the performance or quality.....

I used the BlueSky SB50 in a home installation and have had no problems and don't know about their other products. For the safari, my plans are for high voltage input, which Blue Sky doesn't have a matching product.

I'm looking at the Outback FlexMax or the Morningstar and leaning toward the TS-MPPT-45. I look forward to seeing it in action at the rally.

[Dwight]

I had originally installed a Blue Sky Solar Boost 2000E based on a friends install....it turned out to be too small for my setup and that's when I moved to the Morningstar TS-MPPT-45.

Also, the Blue Sky only is a 3~stage charger vs the Morningstar which is a 4~stage charger.

The physical size and weight between the two controllers is no comparison.....