Solar expansion

[Jmooney]

Finally got the second 100 watt panel installed today.

Chose to place it at the oposite end of the roof to increase odds of taking sunlight when in a shaded campsite.

Renogy " plug and play" adapters work great right out of the box.

Used some puddles of alpha caulk along the cable run to secure cables between two panels, and a wire tie to the AC box at mid point.

I should be producing 14 amps per hour charge rate to my battery array, so on a good day close to 85 amps of charge rate. YEA!

And I sold my generator this week, so I am now officially off the grid

[Ela1948]

You got more guts then me. That genny to me, is like Charlie Brown and his blanket. A measure of security. Happy that works for you. I'm kind of sneaking up on this solar thing with a suitcase style panel arrangement. Back here in the east, there are just too many trees that I want to park under to convince myself that I need them on the roof.

[Mustang65]

Nice job!!! Keep us updated on how they perform.

Don

[Jmooney]

I'm carrying 320 amps of battery power

[rodro123]

This couple the Wynn's have 900 AMPS on the roof this is there latest you tube video

https://www.youtube.com/watch?v=Fj876E1CYVE

[Subaru297]

I am far from an expert but have you calculated your voltage losses with those long wire runs?
Voltage Drop Calculator

Also that front panel looks like it could be shadowed from your Maxair vent cover. That will really reduce the output of that panel. Hard to tell from the picture though.

I have been doing a lot of reading about solar lately as I just ordered a system for our trailer.

The basic consensus is......

Build for no more than 3% voltage drop from the panels to the battery. Short runs with big wires.
Shadows really kill output or potentially drop it to zero even if only one cell out of 36 in the panel is shaded.
Get a programmable charge controller so you can adjust the charge voltage based on battery manufacturer recommendations. Often need 14.8v to battery to fully charge it.

Also 200W of panels is not really enough to keep 320amp/hours of capacity charged.
Check out this resource if you haven't already. Really good information if you can get past all the ranting!
https://handybobsolar.wordpress.com/...ging-puzzle-2/

Cheers

[Timon]

Originally Posted by rodro123

This couple the Wynn's have 900 AMPS on the roof this is there latest you tube video

Actually that's 900 watts not amps.

Can't say I'm in love where they put the batteries. I wouldn't put them under the steps, much better to keep them on the DS IMHO.

Originally Posted by Subaru297

I am far from an expert but have you calculated your voltage losses with those long wire runs?
Voltage Drop Calculator

Also that front panel looks like it could be shadowed from your Maxair vent cover. That will really reduce the output of that panel. Hard to tell from the picture though.

I have been doing a lot of reading about solar lately as I just ordered a system for our trailer.

The basic consensus is......

Build for no more than 3% voltage drop from the panels to the battery. Short runs with big wires.
Shadows really kill output or potentially drop it to zero even if only one cell out of 36 in the panel is shaded.
Get a programmable charge controller so you can adjust the charge voltage based on battery manufacturer recommendations. Often need 14.8v to battery to fully charge it.

Also 200W of panels is not really enough to keep 320amp/hours of capacity charged.
Check out this resource if you haven't already. Really good information if you can get past all the ranting!
https://handybobsolar.wordpress.com/...ging-puzzle-2/

Cheers

They Wynn's run the panels in series so the current draw is less that 8 amps from the panels. Any voltage drop amounts to a very small loss when running in series.

[Dirkdaddy]

Actually its Linus & his blanket

I have two small panels I use b/c I got them surplus cheap use them to keep the 12v battery charged, but thinking of putting in a bigger system. Portable system that folds up sounds good to me but its a hassle and more likely to get stolen / setup hassles, power cord. But you could be under a tree shade.

Still thinking about what I need, as I can boondock w/o a big system as I'm doing short trips for now in the winter here in warm TX and when hooked up don't need it.

Originally Posted by Ela1948

You got more guts then me. That genny to me, is like Charlie Brown and his blanket. A measure of security. Happy that works for you. I'm kind of sneaking up on this solar thing with a suitcase style panel arrangement. Back here in the east, there are just too many trees that I want to park under to convince myself that I need them on the roof.

[Subaru297]

Originally Posted by Timon

Actually that's 900 watts not amps.

Can't say I'm in love where they put the batteries. I wouldn't put them under the steps, much better to keep them on the DS IMHO.


They Wynn's run the panels in series so the current draw is less that 8 amps from the panels. Any voltage drop amounts to a very small loss when running in series.

Running panels in series has its own issues. Any shade or shadow and all your panels are affected. I would much rather have them wired in parallel. You also need a specific charge controller that can handle the higher voltage and some efficiency is lost in lowering that voltage to charge your 12 volt battery. But yes higher volts and lower amps will reduce your voltage drops but it creates other problems.

[Timon]

That's the common believe but it's not totally correct. If one panel gets shaded it basically drops out of the loop but the others still supply power to the solar controller but at a lower voltage. This happens because of the bypass diode located in each panel. Still shading will always causes issues.

In the real world you normally only use solar when boondocking so you try to position your coach to catch the best sun all day. If you're in heavenly wooded area solar won't help much so it doesn't matter.

I'll stay with a series connection as it's much more efficient than parallel connections.

[Seann45]

[QUOTE=Timon;304425]Actually that's 900 watts not amps.

Can't say I'm in love where they put the batteries. I wouldn't put them under the steps, much better to keep them on the DS IMHO.QUOTE]

Those are $2000.00 ea batteries and are truly zero maintenance. That yuppie couple is just to "perky" for me.

[Dirkdaddy]

They sure spent a ton of money. Obviously they are full timing.
I am not sure how they keep the panels from lifting themselves when moving, must be a latch somewhere. I'll have to read on series solar, I was not aware that diodes did more than keep the current from reversing. If the shaded cells just produce zero - and current flows through them efficiently, I can see the logic. For all the cash they spent, seems like someone would offer a nicer front-end to the charge controller and locate it in a better spot, but granted that's close to the equipment.

I really like the wifi extender and the cell repeater if I was to buy a bunch of gear for hanging out working from my TT. But typically I'm just camping and not looking to do "work"

[Timon]

Originally Posted by Dirkdaddy

They sure spent a ton of money. Obviously they are full timing.

They didn't as they don't own the coach. It's basically on loan from the manufacture for a year of testing. They may be paying something but it's not all that much. They are not totally unbiased bloggers when it comes to coaches.

Originally Posted by Dirkdaddy

I am not sure how they keep the panels from lifting themselves when moving, must be a latch somewhere. I'll have to read on series solar, I was not aware that diodes did more than keep the current from reversing. If the shaded cells just produce zero - and current flows through them efficiently, I can see the logic. For all the cash they spent, seems like someone would offer a nicer front-end to the charge controller and locate it in a better spot, but granted that's close to the equipment.

I noticed that too. Those panels have to be lifting plus I didn't see the brackets that hold them at an angle for best sun. Maybe they still had work to do on the coach when they did the video.

Originally Posted by Dirkdaddy

I really like the wifi extender and the cell repeater if I was to buy a bunch of gear for hanging out working from my TT. But typically I'm just camping and not looking to do "work"

WiFi and Cell repeaters in my thinking are a must. That way everything is on your WiFi except your phone when it supplies the WiFi connection to the Internet.

[Jmooney]

Originally Posted by Subaru297

I am far from an expert but have you calculated your voltage losses with those long wire runs?
Voltage Drop Calculator

Also that front panel looks like it could be shadowed from your Maxair vent cover. That will really reduce the output of that panel. Hard to tell from the picture though.

I have been doing a lot of reading about solar lately as I just ordered a system for our trailer.

The basic consensus is......

Build for no more than 3% voltage drop from the panels to the battery. Short runs with big wires.
Shadows really kill output or potentially drop it to zero even if only one cell out of 36 in the panel is shaded.
Get a programmable charge controller so you can adjust the charge voltage based on battery manufacturer recommendations. Often need 14.8v to battery to fully charge it.

Also 200W of panels is not really enough to keep 320amp/hours of capacity charged.
Check out this resource if you haven't already. Really good information if you can get past all the ranting!
https://handybobsolar.wordpress.com/...ging-puzzle-2/

Cheers

Handy Bob is a good read. (despite the political commentary) I read about his design before I started mine last year.

The panels installed produce 19.8 Volts in optimal conditions. They are installed in parallel, so 200 watts at 19.8 volts over 25 foot and 10 foot runs, respectively, on 12ga wire so the loss is under 3%

The Controller is installed in the battery compartment with 12 ga wire to the power buss.

The output side of the controller is definitely producing 14.8 volts, and if left to do its thing, will charge the battery array and move into float mode.

That said, I don't use more than 30-40 amps in a 24 hours period, so the 200 watts can easily keep them re-filled and topped off as needed each day. I am completely LED and only turn on the inverter to watch TV for an hour or two. ( inverter dedicated to entertainment system only )

The front solar panel is set back far enough to avoid most of the shadow issues, but the top of the 5er is so scattered with appliances that its hard to avoid completely. This is partially why I separated the second panel's location from the first, to minimize lost opportunity.

[Subaru297]

Sounds like you did your research and happy to hear it is working for you. Hopefully someone else finds what I wrote useful!

I am in the process of getting a 150W system put together with upgrading potential. Although I might just get two panels right off the bat. I don't really have the batteries to take advantage of that yet though.
I want to get the solar part working first and then upgrade my batteries.

Lot's to learn!

Did you go for a MPPT controller or PWM? I went PWM but after pricing out panels the high voltage (60 cell) panels are about 50cents cheaper per watt. For a 500W system the cost of high voltage panels and MPPT controller is only $50 more expensive than the cheaper PWM controller and more expensive 12V panels.......

[Jmooney]

I have a PWM controller. Not very fancy, but it's doing its job.

My first weekend off the grid and even though the CG had power, we chose to stay unplugged.


We ran a full 24 hours on Friday on battery, allow everyone to use power normally, Including the inverter and TV. Heat on on Friday night ( Colorado and 43 degrees overnight )

Saturday, sun was full on the panels By 10:00am, I had 18.4 volts coming in from the panels, and charging batteries full on, at about 12 amps @ 14.2 volts

Went fishing

Don't know when, but by 7:00pm, charger had moved to float Volatge and dropped to 2.5 amps charging. ( controller set to 14.1 v )

Yea!

[hozerdude]

Originally Posted by Subaru297

Running panels in series has its own issues. Any shade or shadow and all your panels are affected. I would much rather have them wired in parallel. You also need a specific charge controller that can handle the higher voltage and some efficiency is lost in lowering that voltage to charge your 12 volt battery. But yes higher volts and lower amps will reduce your voltage drops but it creates other problems.

I agree 100% Subaru297

[Subaru297]

I spent a bunch of money last weekend and got two 150W panels, a bunch of wire and connectors and two Rolls/Surrette 6v s-290 batteries. Will be installing everything this weekend hopefully. The brains are already mounted on a board.

Excited to see how everything works when it is up and running!

[Subaru297]

Originally Posted by Jmooney

I have a PWM controller. Not very fancy, but it's doing its job.

My first weekend off the grid and even though the CG had power, we chose to stay unplugged.


We ran a full 24 hours on Friday on battery, allow everyone to use power normally, Including the inverter and TV. Heat on on Friday night ( Colorado and 43 degrees overnight )

Saturday, sun was full on the panels By 10:00am, I had 18.4 volts coming in from the panels, and charging batteries full on, at about 12 amps @ 14.2 volts

Went fishing

Don't know when, but by 7:00pm, charger had moved to float Volatge and dropped to 2.5 amps charging. ( controller set to 14.1 v )

Yea!

What batteries do you have? 14.2 volts sounds pretty low for charging completely. Everything I have read says around 14.8 with temperature compensation.
The recommended voltages for the Rolls batteries I just got are;
14.7 Bulk/Absorption
13.14 Float
15.5 Equalization

Although I notice now that with temp compensation it only recommends around 14.2 if the temp is above 28°C or 82°F.

Glad it is working for you though. I hope mine works well too with what I have spec'd out.

Cheers

[Mustang65]

14.2 is fine. In the Florida winter the MPPT Solar charge controller with temperature compensation will go to 14.6 or 14.8 on a cool day (if I put a drain on the batteries the evening before), but 99% of the year it is 14.2.

As for Series vs Parallel, it really depends on how much time your TT is affected by the shading. Where we park for 3 or 4 months (GA Mountains) I have an early morning shade on the back panel and the late afternoon shade affects the front panel, so I will be going parallel. This is one of the reasons I went with the HIGH voltage solar panel (31VDC) and the MPPT Solar Charge controller. It is GREAT in the shade also.

I am in the process of designing a relay switching system for my solar panel output that can be switched between Parallel and Series. Always testing things to see which is better. The nice part about this project is that in the early morning and late afternoon, I can switch between the systems to maximize output. The use of a micro controller to make things easier with the shutdown and start up process. Hmmm, and add a solar intensity sensor.. I can hear DW already....

Have a GREAT DAY!!
Don