250w 30v solar panels

[Sunking]

i meant how many more batteries can i add. 400ah? bulk is set at 28.8v and float is set at 27v

You have to answer that question, we cannot read your mind.

How many watt hours in a day do you need?
What is your location?
Do you have any shade issues? You must have clear view from horizon to horizon to East, South, and West
What time of year operation?

Once you know that information you start the design process. Fail to that that and you will fail and learn a very costly mistake. Sorry but that is just the way it works. It is pure law of physics and physics does not care what you think or want. Like jumping over the moon. No matter how much you want to, it ain't going to happen, physics will not allow you to do that. Physics is not your wire or mother you can BS to get away with something.

[almac]

You have to answer that question, we cannot read your mind.

How many watt hours in a day do you need?
What is your location?
Do you have any shade issues? You must have clear view from horizon to horizon to East, South, and West
What time of year operation?

Once you know that information you start the design process. Fail to that that and you will fail and learn a very costly mistake. Sorry but that is just the way it works. It is pure law of physics and physics does not care what you think or want. Like jumping over the moon. No matter how much you want to, it ain't going to happen, physics will not allow you to do that. Physics is not your wire or mother you can BS to get away with something.

ok. ill take a punt, right now im only discharging 25% of the batteries at night. they charge by midday so il punt i can double from 200ah to 400ah then i can have more of a buffer for rainy days

[Sunking]

ok. ill take a punt, right now im only discharging 25% of the batteries at night. they charge by midday so il punt i can double from 200ah to 400ah then i can have more of a buffer for rainy days

Careful here because FLA batteries have minimum charge current requirements. Double the AH means twice the charge current, which means twice the panel wattage. Right now you are in the season form maximum solar insolation which means your panels should be producing more power than required. That all changes in Winter with short days. Battery systems are designed for worse case which is usually Winter.

[almac]

Careful here because FLA batteries have minimum charge current requirements. Double the AH means twice the charge current, which means twice the panel wattage. Right now you are in the season form maximum solar insolation which means your panels should be producing more power than required. That all changes in Winter with short days. Battery systems are designed for worse case which is usually Winter.

its winter now. im in australia

[russ]

its winter now. im in australia

You mean winter will never come? What Sunking said applies.

[Sunking]

its winter now. im in australia

What I am trying to tell you is FLA batteries have a minimum and maximum charge current requirement window. On the low side generally you need at least a C/12 charge current where C = the battery specified Amp Hour rating, and the number is rate in Hours. Example for a 200 AH battery C/12 = 200 AH / 12 H = roughly 16.7 Amps.

On the high side C/8 so C/8 on the same 200 AH battery is 200 AH / 8 = 25 amps

So if your panel wattage today is say 400 watts with a 24 volt 200 AH battery is generating roughly 17 amps or C/12, and you increase the battery capacity to 400 AH you will not meet the minimum 33 amp minimum requirement of a 400 AH battery. 17 amps on a 400 AH battery is C/24. You would need a panel wattage of 800 watts and a 40 amp controller minimum requirement.

So you tel us, do you have the power and controller to increase battery capacity?

[Bucho]

You mean winter will never come? What Sunking said applies.

No, he means the southern hemisphere's seasons are the opposite of the northern hemisphere's. His winter solstice occurs in June.

[russ]

No, he means the southern hemisphere's seasons are the opposite of the northern hemisphere's. His winter solstice occurs in June.

Again, that means winter never comes? I was depending on people to think - even just a little bit. Winter will still come so he still has to plan for it.

[almac]

What I am trying to tell you is FLA batteries have a minimum and maximum charge current requirement window. On the low side generally you need at least a C/12 charge current where C = the battery specified Amp Hour rating, and the number is rate in Hours. Example for a 200 AH battery C/12 = 200 AH / 12 H = roughly 16.7 Amps.

On the high side C/8 so C/8 on the same 200 AH battery is 200 AH / 8 = 25 amps

So if your panel wattage today is say 400 watts with a 24 volt 200 AH battery is generating roughly 17 amps or C/12, and you increase the battery capacity to 400 AH you will not meet the minimum 33 amp minimum requirement of a 400 AH battery. 17 amps on a 400 AH battery is C/24. You would need a panel wattage of 800 watts and a 40 amp controller minimum requirement.

So you tel us, do you have the power and controller to increase battery capacity?

ok thanks for the info, my panels are rated at 750w. at this time right now (winter) my panels are delivering about 18amps at 34v so about 600w , at 24v 600w this would be 25amps to the batteries for about 4 hrs 10am to 2pm, another 4hrs either side of this time they are delivering about 10amps or 340w at 24v about 14amps ie 8am to 10pm and 2pm to 4pm then its sundown. so i guess i only have enough panel to deliver charge for a 200ah battery bank, so wont increase battery bank. thankyou.

[Bucho]

Again, that means winter never comes?

No, because it's already here. Next month is the worst so he can ignore it and base things on NOW and July.