DIY 60 watt Folding Solar Panel

[mikeschn]

Those are really good prices. Are you sure they are sale prices? They look like everyday pricing to me!

Mike...

UL solar is having a sale on panels. Cheapest I've ever seen. I've had to get some extra connectors as my current controller has different connects on it.

I got the 85 watt one!!

http://www.ul-solar.com/85_Watt_12_Volt ... 5p-tls.htm

[Ratkity]

Those are really good prices. Are you sure they are sale prices? They look like everyday pricing to me!

Mike...

They've been "on sale" for a while. Still the cheapest I've seen. I'd avoid the "kits" though. I already have a controller and need to figure out mounts.

Hugs,
Ratkity

[mikeschn]

Bruce,

Can you recommend a controller that lets me see how many watts or amps per hour I actually put into the battery, and how many watts or amps I actually took out?

Mike...

[bdosborn]

Mike,

Blue Sky makes battery monitor that will plug into one of their controllers the IPN Pro remote. You still have to buy a controller to go with it so its expensive (MSRP=$500 for monitor and controller). Maybe someone else knows of one?

The Sunsaver Duo comes with a meter that will monitor the solar panel amp-hrs but not the total battery amp-hrs. Its also setup for a motor home so it will charge two different battery banks so your buying a controller that does more than most Teardroppers need. It does have good capacity with a 25 amp rating.

The Sunsaver MPPT has an add on monitor that will track amp-hrs from the array as well as amp-hrs to a load but it doesn't totalize it and you would have to limit your 12V loads to the 15 amp capacity of the controller. Once again, its pretty high dollar (MSRP=$350). It's the meter on the left in the picture below.

I use a Trimetric 2025-RV battery monitor from Bogart Engineering:
Battery Monitor Linky. Its the meter on the right in the photo below:



Its not built into the solar controller but it totalizes amp-hrs in and out from the battery. It was the most accurate for the least money when I was researching monitors but its still not cheap. I think I got mine for $170 including the shunt. I really like it, I can tell at glance where I'm at battery capacity wise. Its as simple as if the meter says 50% down, its time to charge the battery. Mine has a 100 amp shunt so I can run the inverter through it as well. They have a 500 amp option but it's less accurate.

I would use a Sunsaver (SS) 10 for up to 150 watts of PV or a SS 20 for up to 300 watts and use a Trimetric meter if I was doing it over again. I started with a SS 10 but added another panel and maxed out my controller. I upgraded to a SS MPPT but I don't think its worth the extra bucks for most people.

The Trimetric is expensive but I won't ever have a trailer without one, I like it that much. The SS MPPT monitor I'd probably do without if I was doing it again.

Bruce

Rogue MPPT Controller is the current favorite small controller over at the solar forum.

[chorizon]

I thought about getting a "Doc Wattson" digital ammeter and plumbing it so that I could measure the charging/discharging of my battery.

It has a very low draw on the battery (.007A).

I assume if I have no loads drawing power from my battery the indicated current would be what my panels are putting into the battery.

This seems like the cheapest solution for me to monitor panel output, am I missing something?

I'm a newb to solar BTW, I'm still tinkering/fascinated with my 45W Harbor Freight kit.

I hinged them together like you did and am about to mount them on a swiveling pedestal.

[Ratkity]

I don't have a monitor, just the sunforce 7 - maxes at 100w of panels with 7 amp array (more than my 85watt will be when it gets here).

It was fairly cheap ($17 amazon) and came with my 15w solar panel battery monitor kit.

Hugs,
Ratkity

Edited for correct spelling of product.

[bdosborn]

I thought about getting a "Doc Wattson" digital ammeter and plumbing it so that I could measure the charging/discharging of my battery.

Hey I forgot about those. Someone else was using one on their PV array on a cargo trailer and I think they were happy with it. I bought one to play with but lost it in the garage somewhere. Hope I find it soon...

Bruce

[chorizon]

My HF 45W kit came with a charge controller, which I know I'll replace at some point after the initial field-tests (it doesn't look very weatherproof).

I'll definitely look at the Sunforce 7, that's a great price, thanks for the link, Ratkity!

Here's the Doc Wattson ammeter:
At $60, it seems to be the most reasonably priced digital ammeter.
http://www.powerwerx.com/tools-meters/doc-wattson-meter-dc-inline.html


<edit> You posted before I hit "submit"! Thanks, Bruce for confirming my thought to use this 'lil baby!

[bdosborn]

I remember now why I didn't go with this one, it has a continuous rating of 50 amps, which is too small to use with my inverter. But it should work nicely for an electrical system that doesn't need to use/monitor an inverter. One thing I didn't like is that the entire load current flows through the meter so you might loose all power you overloaded it and let the smoke out.

Bruce

[chorizon]

Thanks, Bruce I won't have anywhere near 50A going to/from my battery so I guess I'll be safe.

Worse case scenario if the smoke escapes from this little unit, it still would be pretty easy to remove it and get the power going again.

I just noticed on Amazon the Sunforce 30 A charge controller displays current ratings and costs $83. Any experience with these? The reviews are mostly favorable...

Is it a bad idea to use such a large controller (30 A) with smaller output panels (like my 45W)?
http://www.amazon.com/Sunforce-60032-Digital-Charge-Controller/dp/B000FIWKQE/ref=sr_1_1?ie=UTF8&qid=1304896620&sr=8-1

[bdosborn]

I'll definitely look at the Sunforce 7, that's a great price, thanks for the link,

I would look at the Sunguard controller if you're looking for an inexpensive controller. 4.5 amps for $23. Its also outdoor rated and fully potted. Oh and its a Morningstar, I kind of like their stuff.

Bruce

[chorizon]

Yes that looks slick. Compact and to the point!

Thanks!

[bdosborn]

I just noticed on Amazon the Sunforce 30 A charge controller displays current ratings and costs $83. Any experience with these? The reviews are mostly favorable...

Is it a bad idea to use such a large controller (30 A) with smaller output panels (like my 45W)?

I don't know anything about the Sunforce other than cheap controllers make me suspicious. I also don't like poor documentation and it doesn't look like there's any at all for the Sunforce.

Its a great idea to get a larger controller if you even think you'll expand your system someday. That way you only need to buy a controller once. I had to buy two because I didn't plan very well for growth.

Bruce

[Ratkity]

Dang you Bruce!

This solar stuff is addicting!!!! LOL

Hugs,
Ratkity

[Ratkity]

It's done!!



I also made a cover a-la the foamie TD style:



The cover is VERY light and sturdy; only to be used while traveling to avoid road debris and rocks.

Hugs,
Raktity