Solar Charge Controller question

babock wrote:

StirCrazy wrote:
good one, notice how they don't show perfect weather... two reasons, 1 much smaller difference between the two, and
2 when do you every have perfect weather when you camp ;)

the only thing I wish they would have shown is when trees cast shadows over the pannel so you have 1/2 the pannel shadowed out, that's the biggest difference.

Steve

Gotta love the BS that people think. He tested it with the weather he had at the time. Was May in Maine!

I actually like that test, so not sure what your going on about. I just wish he had good weather so he could test the difference when it was partial shaded to show where the MPPT really shines. I have always said the MPPT is a better unit if you are set up properly, hence why I am building my campers system with a MPPT instead of the PWM they put on my 5th wheel.

Steve

StirCrazy wrote:
good one, notice how they don't show perfect weather... two reasons, 1 much smaller difference between the two, and
2 when do you every have perfect weather when you camp ;)

the only thing I wish they would have shown is when trees cast shadows over the pannel so you have 1/2 the pannel shadowed out, that's the biggest difference.

Steve

Gotta love the BS that people think. He tested it with the weather he had at the time. Was May in Maine!

bpounds wrote:
Worked for me. This is the first link offered.
Tested PWM versus MPPT

Here is the short and sweet of it:

good one, notice how they don't show perfect weather... two reasons, 1 much smaller difference between the two, and
2 when do you every have perfect weather when you camp ;)

the only thing I wish they would have shown is when trees cast shadows over the pannel so you have 1/2 the pannel shadowed out, that's the biggest difference.

Steve

Worked for me. This is the first link offered.
Tested PWM versus MPPT

Here is the short and sweet of it:

Babock,

Great!

A link that takes me to a test of tires. LOL you certainly do know how to help others learn.

I was hoping that with your VAST knowledge, you would know of some non laboratory real life testing.

pianotuna wrote:
Let's see a link.

https://lmgtfy.com/?q=Compare+the+performance+of+PWM+vs+MPPT

babock wrote:

pianotuna wrote:

babock wrote:
All I did was give an example of performance for a PWM vs MPPT for an example 100W 20V solar panel. I didn't put a cost comparison..just a technical operating difference. Those were factual numbers....not an opinion.

And all I'm suggesting is that you post a link to that testing and those numbers.

LOL...if you don't understand the math how an MPPT or a PWM work, there are a lot of sites that will explain it to you. I couldn't explain it any simpler. BTW EE here. I have done designs using both methods of controlling voltages/currents for years. It's not something new.

Let's see a link.

I'm perfectly aware of the differences between MPPT and PWM.

bpounds wrote:
We shouldn't even be having the PWM vs MPPT discussions these days. The info is out there for anyone who wants to even briefly study the question.

Price difference is so small now that PWM only makes sense for the smallest system, and when there is no chance for future increase.

You might even save most of the cost difference by using smaller conductors and higher voltage if there are more than 2 panels in the array. And who doesn't want as much energy as possible out of their investment?

Exactly. The only time I would buy a PWM controller, which I just did, was for a simple small wattage panel to keep my boat battery topped off while it is sitting at my dock.

pianotuna wrote:

babock wrote:
All I did was give an example of performance for a PWM vs MPPT for an example 100W 20V solar panel. I didn't put a cost comparison..just a technical operating difference. Those were factual numbers....not an opinion.

And all I'm suggesting is that you post a link to that testing and those numbers.

LOL...if you don't understand the math how an MPPT or a PWM work, there are a lot of sites that will explain it to you. I couldn't explain it any simpler. BTW EE here. I have done designs using both methods of controlling voltages/currents for years. It's not something new.

We shouldn't even be having the PWM vs MPPT discussions these days. The info is out there for anyone who wants to even briefly study the question.

Price difference is so small now that PWM only makes sense for the smallest system, and when there is no chance for future increase.

You might even save most of the cost difference by using smaller conductors and higher voltage if there are more than 2 panels in the array. And who doesn't want as much energy as possible out of their investment?