600W Solar - Getting 420W Max

This is EXACTLY WHY endless stabbing a calculator to try and PLAN EXACTLY a solar system is utter futility. Ya goes with the flow and add panels as needed.

2oldman wrote:
Is your converter off?

Converter is off, except when I need the extra boost when it get to cloudy or raining.

Thanks for everyone's input. Guess it is working like it should. Gary

RoyB wrote:
I'm hoping my OFF-ROAD POPUP roof will allow me to install two 120WATT panels in the front along side of the Fantastic Fan and maybe a 240WATT panel on the rear of the roof just behind the roof mounted air conditioner..

All I am looking for is a good 20AMPS plus during the high sun to supplement my battery charging when using the 2KW Generator each day when camping off the power grid. My daily draw from the batteries usually starts at 6PM to 11PM where we will pull a good 20AMPS or so continuous. Then of course we always have our 1-2AMPS of parasitic drains. All of this drops my current battery banks of 255AHs capacity down to the 12.0VDC level at 8AM each morning which is around the 50% charge state. This is when I want to start my re-charge using my 2KW generator to power up the PD9260C converter/charger for my three hour run. Using the planned solar panels I think I will be able to only need the generator for the first one hour charge run.

Being always around public camp grounds here on the east side of the US that seem to all have generator run time restrictions I need to get my batteries re-charged as quick as possible each day...

My battery bank will want to draw around 50AMPS PLUS DC current when first hit with 14.4VDC which make me have to use the generator for sure until the charge current starts tapering back. When it gets to the 8AMPS DC Current demand than I can stop using the generator and let the solar panels finish my re-charge state with my daily goal being 90% charge state before I run out of high sun each day.

I should be able to do this with the 20AMPS DC Current with high sun...

Some say I will do better than this which is great. I still will have to keep both systems of charge however as I will not even think about starting my day/night run off of the batteries unless I have a 90% charge state. Everytime I do this it always gets dark on me around 10PM at night. When my DC VOLTS monitor panels its 12.0VDC I shut down the batteries until i can run the generartor again.

I'm still in the planning and thinking stage here haha...

When I get my newer batteries soon I will have to get going with this project...

Sounds like you are doing great with your new solar setup...

Roy Ken

So far I have been able to charge my batteries back before sun set. I do draw a lot from them during the 24hrs. I run a 32" led &19"led tv, which I watch until 12 or 1 in the morning, and have a 12v freezer. I have been in TX for 34 day. Only had to turn on the converter 2 times, for rain and heavy clouds. Its been a big difference from back home in NE. I never had this kind of output from the solar. I am very happy (wish I had more free roof space.) Gary

I'm hoping my OFF-ROAD POPUP roof will allow me to install two 120WATT panels in the front along side of the Fantastic Fan and maybe a 240WATT panel on the rear of the roof just behind the roof mounted air conditioner..

All I am looking for is a good 20AMPS plus during the high sun to supplement my battery charging when using the 2KW Generator each day when camping off the power grid. My daily draw from the batteries usually starts at 6PM to 11PM where we will pull a good 20AMPS or so continuous. Then of course we always have our 1-2AMPS of parasitic drains. All of this drops my current battery banks of 255AHs capacity down to the 12.0VDC level at 8AM each morning which is around the 50% charge state. This is when I want to start my re-charge using my 2KW generator to power up the PD9260C converter/charger for my three hour run. Using the planned solar panels I think I will be able to only need the generator for the first one hour charge run.

Being always around public camp grounds here on the east side of the US that seem to all have generator run time restrictions I need to get my batteries re-charged as quick as possible each day...

My battery bank will want to draw around 50AMPS PLUS DC current when first hit with 14.4VDC which make me have to use the generator for sure until the charge current starts tapering back. When it gets to the 8AMPS DC Current demand than I can stop using the generator and let the solar panels finish my re-charge state with my daily goal being 90% charge state before I run out of high sun each day.

I should be able to do this with the 20AMPS DC Current with high sun...

Some say I will do better than this which is great. I still will have to keep both systems of charge however as I will not even think about starting my day/night run off of the batteries unless I have a 90% charge state. Everytime I do this it always gets dark on me around 10PM at night. When my DC VOLTS monitor panels its 12.0VDC I shut down the batteries until i can run the generartor again.

I'm still in the planning and thinking stage here haha...

When I get my newer batteries soon I will have to get going with this project...

Sounds like you are doing great with your new solar setup...

Roy Ken

"About the only time you'd see the full 600W is at noon on the equator. "

at 60 degrees Fahrenheit!

About the only time you'd see the full 600W is at noon on the equator.

Not sure what you mean by "gains", but you will see more amps output from MPPT when the battery voltage is lower.

If that 420w is output, divide that by the battery voltage and that will be your charging amps at the moment. Same output watts but with the battery voltage higher, fewer amps.

420/12.4 = 34 amps, so if you are seeing 30 amps with 420w out, battery voltage would be higher at 14 volts

Is your converter off?

Your numbers are good. At maximum sun add heavy loads to see what your controller will produce. I got 49A out of 750W, clear day in March in Phoenix, flat mounted panels with MPPT controller.

"I see my gains on the solar seem to go with how low I draw the batteries down and how much I use during the day."

That's normal as the controller will not produce unneeded power.

As a test since you have utility power you could draw more power than the solar can produce all day to see the numbers and then turn on the charger at night.