currently have a 160w folding solar panel that connects to my 130ah agm battery.
have purchased (and awaiting delivery) of a mppt controller to replave the pwm that is currently on the panels.
question is, currently the panels wired in parallel into the pwm. should i be changing this to have the panels in series into the mppt or is it ok as parallel?
thanks
Jaahn said
06:14 PM Apr 7, 2021
Hi Bribi
You could wire them in series. There is a small advantage in some situations but not much really for a small setup. What are the specs of the panels.
Secondly now is the time to fit the regulator near the battery instead of on the panels !! That will possibly give you a better working setup.
Thirdly! Note that cheap MPPT regulators are mostly fakes ! and are really PWM regs with a fancy sticker. You have been warned. If so then series wiring your two panels will loose half their power most of the time !
Jaahn
Whenarewethere said
06:53 PM Apr 7, 2021
As said above.
I have a portable setup 6 x 20 watt panels. I have tested them 6 in parallel, 2 in series in 3 parallel sets & 3 in series in 2 parallel sets.
I didn't test them long enough to see if there was any noticeably difference. In the end I stuck with the manufacturer's recommendation of 2 in series.
The advantage of this is that early in the morning or on non ideal days you will get a bit more power.
But the key thing is to put the controller near the battery & plug the panels in & have some cables for extention so the panel do not get any shadows. A very small shadow will dramatically reduce output.
Thanks for that info. They are regular panels so should work OK. What is the regulator type and spec you are getting.
In a past time I had some portable panels but found them too heavy to handle, getting them in and out etc. So I just disconnected the hinges and rewired them so they could be used singly or together. And I made a long extension cord to use if needed to chase the sun easier. But I did fit the reg near the battery. Later I set it up for 4 panels wired 2 in series x 2 strings into a MPPT reg all individually plugging into a junction box.
Jaahn
Mike Harding said
08:29 AM Apr 12, 2021
Jaahn wrote:Thirdly! Note that cheap MPPT regulators are mostly fakes ! and are really PWM regs with a fancy sticker.
In regard to product sourced from Ebay and the like I agree with Jaahn.
Having run a (genuine) MPPT controller on 180W of panels for a few years now I'm not convinced they are worth the extra cost over a quality PWM controller - although they probably generate less RF emission which is a good thing.
Do check carefully that your new controller actually operates as it should and that it produces (close to) the maximum current the panels can generate. I bought a folding pair of 140W panels which came with a controller, even in good sun that controller only produced about 3A - replacing it with a quality PWM the current increased to about 8A! The Ebay supplier told me I didn't know what I was doing however with 40 years of electronics design behind me I rather think I do :)
dorian said
08:38 AM Apr 12, 2021
Jaahn wrote:
Note that cheap MPPT regulators are mostly fakes ! and are really PWM regs with a fancy sticker.
MPPT = Most Probably Pwm Trash
dorian said
08:41 AM Apr 12, 2021
Mike Harding wrote:
I bought a folding pair of 140W panels which came with a controller, even in good sun that controller only produced about 3A - replacing it with a quality PWM the current increased to about 8A!
If the controller was fake, then I would be concerned about the "140W" panels. That said, 8A seems about right for PWM.
-- Edited by dorian on Monday 12th of April 2021 08:46:01 AM
Mike Harding said
09:35 AM Apr 12, 2021
dorian wrote:
Mike Harding wrote:
I bought a folding pair of 140W panels which came with a controller, even in good sun that controller only produced about 3A - replacing it with a quality PWM the current increased to about 8A!
If the controller was fake, then I would be concerned about the "140W" panels. That said, 8A seems about right for PWM.
Indeed, so was i! But the panels are fine and have been in use for a few years and, via the MPPT, produce about 9A on a good summer day. A shame the supplier was prepared to ruin a good system for the sake of spending another $5 or $10 on a better controller. I suppose they rely upon the concept that most people will never know, they'll just think "these new-fangled solar panels are not as good as I hoped."
Bribri said
07:31 PM Apr 12, 2021
Sorry got sidetracked. The reg is a kings 20a mppt. Currently wired the panels in parallel. But ran out of sunlight to check power outputs.
Mike Harding said
07:50 PM Apr 12, 2021
I have heard many good things about Kings solar products and no bad things so I suspect you'll be OK.
currently have a 160w folding solar panel that connects to my 130ah agm battery.
have purchased (and awaiting delivery) of a mppt controller to replave the pwm that is currently on the panels.
question is, currently the panels wired in parallel into the pwm. should i be changing this to have the panels in series into the mppt or is it ok as parallel?
thanks
Hi Bribi
You could wire them in series. There is a small advantage in some situations but not much really for a small setup. What are the specs of the panels.
Secondly now is the time to fit the regulator near the battery instead of on the panels !! That will possibly give you a better working setup.
Thirdly! Note that cheap MPPT regulators are mostly fakes ! and are really PWM regs with a fancy sticker. You have been warned.
If so then series wiring your two panels will loose half their power most of the time !
Jaahn
As said above.
I have a portable setup 6 x 20 watt panels. I have tested them 6 in parallel, 2 in series in 3 parallel sets & 3 in series in 2 parallel sets.
I didn't test them long enough to see if there was any noticeably difference. In the end I stuck with the manufacturer's recommendation of 2 in series.
The advantage of this is that early in the morning or on non ideal days you will get a bit more power.
But the key thing is to put the controller near the battery & plug the panels in & have some cables for extention so the panel do not get any shadows. A very small shadow will dramatically reduce output.
I'm using a Victron 100/20 MPPT.
Thanks for that info.
They are regular panels so should work OK. What is the regulator type and spec you are getting.
In a past time I had some portable panels but found them too heavy to handle, getting them in and out etc. So I just disconnected the hinges and rewired them so they could be used singly or together. And I made a long extension cord to use if needed to chase the sun easier. But I did fit the reg near the battery. Later I set it up for 4 panels wired 2 in series x 2 strings into a MPPT reg all individually plugging into a junction box.
Jaahn
In regard to product sourced from Ebay and the like I agree with Jaahn.
Having run a (genuine) MPPT controller on 180W of panels for a few years now I'm not convinced they are worth the extra cost over a quality PWM controller - although they probably generate less RF emission which is a good thing.
Do check carefully that your new controller actually operates as it should and that it produces (close to) the maximum current the panels can generate. I bought a folding pair of 140W panels which came with a controller, even in good sun that controller only produced about 3A - replacing it with a quality PWM the current increased to about 8A! The Ebay supplier told me I didn't know what I was doing however with 40 years of electronics design behind me I rather think I do :)
MPPT = Most Probably Pwm Trash
If the controller was fake, then I would be concerned about the "140W" panels. That said, 8A seems about right for PWM.
-- Edited by dorian on Monday 12th of April 2021 08:46:01 AM
Indeed, so was i! But the panels are fine and have been in use for a few years and, via the MPPT, produce about 9A on a good summer day. A shame the supplier was prepared to ruin a good system for the sake of spending another $5 or $10 on a better controller. I suppose they rely upon the concept that most people will never know, they'll just think "these new-fangled solar panels are not as good as I hoped."
I have heard many good things about Kings solar products and no bad things so I suspect you'll be OK.