Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 16-07-2014, 17:11   #1
Registered User
 
zboss's Avatar

Join Date: Sep 2011
Location: On a boat
Boat: Cabo Rico 38
Posts: 3,426
Outback 60 with Partially Shaded Panels

Hi,

If want to use a single Outback Flexmax 60 charge controller with four solar panels, I assume that the four panels will be wired in parallel to a bus, which then goes to the controller.

If some of those panels are shaded, while others are not, how will this effect the overall voltage of the system?

Is this an effective method of using our panels? I expect that at least 1 or 2 panels will be shaded during certain parts of the day.

- z
__________________

__________________
zboss is offline   Reply With Quote
Old 19-07-2014, 09:27   #2
Registered User
 
zboss's Avatar

Join Date: Sep 2011
Location: On a boat
Boat: Cabo Rico 38
Posts: 3,426
Re: Outback 60 with partially shaded panels

The reason I bring this up is that I currently have one controller for each panel and I wanted to know what kind of difference I could expect.
__________________

__________________
zboss is offline   Reply With Quote
Old 19-07-2014, 19:16   #3
Moderator Emeritus
 
Ex-Calif's Avatar

Cruisers Forum Supporter

Join Date: May 2007
Location: Singapore
Boat: Maxi 77 - Relax Lah!
Posts: 11,514
Images: 4
Re: Outback 60 with partially shaded panels

I haven't reread this lately but with lots of solar, high voltage controller and series is the way to go.

The controller has a better chance of being able to deliver charge voltage when cells are shaded. Although, of course amperage still suffers.

W = V X I
__________________
Relax Lah! is For Sale <--- Click
Click--> Custom CF Google Search or CF Rules
You're gonna need a bigger boat... - Martin Brody
Ex-Calif is offline   Reply With Quote
Old 19-07-2014, 19:23   #4
Registered User

Join Date: Oct 2011
Location: Winter Bahamas - Summer BC
Boat: Lagoon 450, Bavaria Vision 40
Posts: 615
Re: Outback 60 with partially shaded panels

I run 3 panels in parallel and another 3 in series, each set on one Outback 60. So far I have not seen any significant differences in the daily output averages. Some days the parallel is better, some days the series string. I stll have a plan to do do some detailed test with the set up.
__________________
roetter is offline   Reply With Quote
Old 19-07-2014, 19:27   #5
Registered User

Join Date: Mar 2010
Location: Wandering around North America
Boat: Defever 43 - Gray Hawk
Posts: 602
Re: Outback 60 with partially shaded panels

My advice plus $5 will buy coffee pretty well anywhere in North America but for identical panels I'd wire them in series to an MPPT controller. I think there's a case to be made that they will be more efficient and less subject to shading. Even if none of that is true you will be able to use lighter gauge wire.


R.J.(Bob) Evans
www.travellingwithgeorge.blogspot.com
__________________
R.J.(Bob) Evans
M/V Gray Hawk, 43 Defever Offshore Cruiser
http://www.bobandmarilyn.ca
bobofthenorth is offline   Reply With Quote
Old 19-07-2014, 21:46   #6
Marine Service Provider

Join Date: Sep 2008
Location: Victoria B.C.
Boat: CS27
Posts: 1,725
Re: Outback 60 with partially shaded panels

Series works well on land where the panels can be installed with no shading issues. In any installation with shading parallel is the choice to make. Shading a series array kills it. Shading a parallel array reduces output by the shaded panel but not the rest of the un-shaded panels.
__________________
mitiempo is offline   Reply With Quote
Old 20-07-2014, 03:19   #7
Registered User
 
Hkalan's Avatar

Join Date: Nov 2011
Location: Hong Kong
Boat: Bertram 46.6 FBMY
Posts: 285
Re: Outback 60 with partially shaded panels

Hello,

Parallel is by far the best.

I use a Morningstar TS-60 MPPT with a combiner box I made that breaks the + and - to isolate any panel.

Click image for larger version

Name:	ImageUploadedByCruisers Sailing Forum1405847900.847280.jpg
Views:	244
Size:	221.9 KB
ID:	85246
Click image for larger version

Name:	ImageUploadedByCruisers Sailing Forum1405847928.343427.jpg
Views:	226
Size:	203.1 KB
ID:	85247
Click image for larger version

Name:	ImageUploadedByCruisers Sailing Forum1405847950.232543.jpg
Views:	198
Size:	230.4 KB
ID:	85248
__________________
Hkalan is offline   Reply With Quote
Old 20-07-2014, 04:56   #8
Moderator Emeritus
 
Ex-Calif's Avatar

Cruisers Forum Supporter

Join Date: May 2007
Location: Singapore
Boat: Maxi 77 - Relax Lah!
Posts: 11,514
Images: 4
Re: Outback 60 with partially shaded panels

Quote:
Originally Posted by mitiempo View Post
Series works well on land where the panels can be installed with no shading issues. In any installation with shading parallel is the choice to make. Shading a series array kills it. Shading a parallel array reduces output by the shaded panel but not the rest of the un-shaded panels.
Thanks mitempo you are correct - I made a mistake in my post.

Thanks for chiming in.
__________________
Relax Lah! is For Sale <--- Click
Click--> Custom CF Google Search or CF Rules
You're gonna need a bigger boat... - Martin Brody
Ex-Calif is offline   Reply With Quote
Old 20-07-2014, 05:03   #9
Moderator
 
noelex 77's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Location: Living on dirt waiting for our new yacht to be built.
Boat: Half built Bestevaer.
Posts: 10,618
Re: Outback 60 with partially shaded panels

Quote:
Originally Posted by zboss View Post
The reason I bring this up is that I currently have one controller for each panel and I wanted to know what kind of difference I could expect.
One controller for each panel gives superior tracking, but the difference is small. The other problem is that the good MPPT controllers have reasonably high self consumption so you can lose more than you gain.

A single good quality controller is the norm and works well.

As you can see there is a lot of debate between series and parallel connection. Unfortunately I don't think there is enough evidence to form a definitive answer, but mine are wired in parallel.
__________________
noelex 77 is offline   Reply With Quote
Old 20-07-2014, 10:00   #10
Don't ask if you can't handle it
 
sailorboy1's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Location: On the boat somewhere
Boat: Hunter 410
Posts: 12,308
Re: Outback 60 with partially shaded panels

I bet that if multiple panels are smaller 12V panels that wired in series is best. But if higher voltage panels like 24-36V panels that it doesn't matter much.


Sent from my iPhone using Cruisers Sailing Forum
__________________
jobless, houseless, clueless, living on a boat and cruising around somewhere
sailorboy1 is online now   Reply With Quote
Old 20-07-2014, 11:10   #11
Registered User
 
Dulcesuenos's Avatar

Join Date: Dec 2010
Location: Florida Keys, Bahamas Bound
Boat: 38' French Cat
Posts: 2,828
Images: 4
Re: Outback 60 with partially shaded panels

We have 6 panels paralleled together, no combiner box, to one controller, and very pleased with it

Sent from my LG-LS980 using Cruisers Sailing Forum mobile app
__________________
Dulcesuenos is online now   Reply With Quote
Old 20-07-2014, 14:21   #12
Marine Service Provider

Join Date: Sep 2008
Location: Victoria B.C.
Boat: CS27
Posts: 1,725
Re: Outback 60 with partially shaded panels

Quote:
Originally Posted by sailorboy1 View Post
I bet that if multiple panels are smaller 12V panels that wired in series is best. But if higher voltage panels like 24-36V panels that it doesn't matter much.
Wired in series a shaded panel is a roadblock. Not unlike the old series Christmas tree bulbs. Parallel will not stop a good output panel from passing through the connections of a shaded panel. In series the current has to pass totally through the shaded panel, which it cannot do. Pretty basic really.

Now on a powerboat's upper deck without any possibility of shadowing series works well.
__________________
mitiempo is offline   Reply With Quote
Old 20-07-2014, 15:11   #13
Moderator
 
noelex 77's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Location: Living on dirt waiting for our new yacht to be built.
Boat: Half built Bestevaer.
Posts: 10,618
Re: Outback 60 with partially shaded panels

Quote:
Originally Posted by mitiempo View Post
In series the current has to pass totally through the shaded panel, which it cannot do. Pretty basic really.
All solar panels have bypass diodes. As the name suggests these function to bypass the current around the shaded cells (with some losses).
__________________
noelex 77 is offline   Reply With Quote
Old 20-07-2014, 18:09   #14
Registered User
 
zboss's Avatar

Join Date: Sep 2011
Location: On a boat
Boat: Cabo Rico 38
Posts: 3,426
Re: Outback 60 with Partially Shaded Panels

I was observing our panels and because of the limitations on our cabo, we only see 1 out of 4 panels completely unshaded during the day, except for about an hour on each end at peak solar high, during which we have four panels going string. The 4th panel then becomes the primary panel when the sun moves across the sky or we swing due to current.
__________________
zboss is offline   Reply With Quote
Old 20-07-2014, 18:17   #15
Marine Service Provider

Join Date: Sep 2008
Location: Victoria B.C.
Boat: CS27
Posts: 1,725
Re: Outback 60 with partially shaded panels

Quote:
Originally Posted by noelex 77 View Post
All solar panels have bypass diodes. As the name suggests these function to bypass the current around the shaded cells (with some losses).
For a 36 cell panel there are usually 2 bypass diodes. Still adds up to a loss if multiple panels are in series. Parallel doesn't have any issues with current from one panel passing a shaded panel.
__________________

__________________
mitiempo is offline   Reply With Quote
Reply

Tags
panels

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Solar panels that will be partially shaded--which is better? autumnbreeze27 Electrical: Batteries, Generators & Solar 16 02-02-2014 15:21
Heart,Trace,Xantrex,Outback,Mangum,Midnight Solar What they all have in common... FlyingCloud1937 Electrical: Batteries, Generators & Solar 1 16-03-2013 11:28
Partially-Built-Cat Info, Please barrynash Multihull Sailboats 6 12-07-2010 11:55
Best sources for Kyoceras and Outback controllers? gbanker Electrical: Batteries, Generators & Solar 4 19-11-2008 17:50
Outback 60 RFI Wahoo Sails Marine Electronics 2 01-05-2007 15:42



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 06:08.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.