Problem only the professional people in this forum can fix it please help

[paulcheung]

My friend

As you told me i must consider the hour rate on battery ampere size
Just as explain about battery bank capacity i need to know something i was thinking of last night

12v 250ah*8 parallel type = 48v 500AH total ampere in battery bank is 2000ah
6v 250ah *16 parallel type=48v 500Ah total ampere in battery bank is 4000ah

I am so sorry for this question but i have no experience and i do not find any other person help me to understand so i need your help

What you calculate is partial wrong,

12 volts 250ah x8 is 96 volts 250ah or 48volts 500ah or 24 volts 1000ah or 12volts 2000ah.

6 volts 250ah x16 is 96 volt 250ah or 48volts 500ah or 24 volts 1000ah or 12 volts 2000ah or 6 volts 4000ah.

Your battery options is better you either use option #1, 8 12volts 250ah AGM wired 4 in series and parallel two string make it 48 volts 500ah.

You other option is #3 16 6volts 380ah wired 8 in a series and parallel the two strings make 48 volts 760ah. this will last longer and give you more power in case the grid don't come as planned in two hours.

#2 option will be under power as the batteries are not AGM and it will stress the batteries too much, the charging rate is over C8 rate and the discharge rate is also over the C8 rate.

#4 option is way over kill, at 3000ah you have problem to recharge the battery bank properly. and this option will cost you a lot of $$$$$$.

Cheers

[Lacosteiq]

What you calculate is partial wrong,

12 volts 250ah x8 is 96 volts 250ah or 48volts 500ah or 24 volts 1000ah or 12volts 2000ah.

6 volts 250ah x16 is 96 volt 250ah or 48volts 500ah or 24 volts 1000ah or 12 volts 2000ah or 6 volts 4000ah.

Your battery options is better you either use option #1, 8 12volts 250ah AGM wired 4 in series and parallel two string make it 48 volts 500ah.

You other option is #3 16 6volts 380ah wired 8 in a series and parallel the two strings make 48 volts 760ah. this will last longer and give you more power in case the grid don't come as planned in two hours.

#2 option will be under power as the batteries are not AGM and it will stress the batteries too much, the charging rate is over C8 rate and the discharge rate is also over the C8 rate.

#4 option is way over kill, at 3000ah you have problem to recharge the battery bank properly. and this option will cost you a lot of $$$$$$.

Cheers

My friend thank you for this explain but what i mean is when i use 12v 250AH *8= 48v 500Ah bank power is 2000amp
And the 6v 250*16= 48v 500AH bank power is 4000
What is the benefit of the total power bank when the hour rate is the same 500AH in 12v and the 6v
Is the 4000Ah = 2000ah

Regards

[paulcheung]

I am not sure what do you mean and what is the question is. but you do know 8 of the 12 volts 250 ah batteries is equal to 16 6 volts 250 ah batteries in capacity.

They make different size and voltage for different purposes, they make larger amperage with lower volt so the weight of one battery can be manage by a single man, they are try to avoid parallel strings so they make different amps hours with different voltage. 2 volts, 4 volts, 6 volts, 8 volts and 12 volts. FLA batteries are 2 volts cells, that is why you don't see 5 volt or seven volts. They reason is for weight management so you don't have to move a 2000 pounds battery.

[paulcheung]

The power company and the electrical professionals using Watts or watt hours to record the consumption and capacity. They don't use amperes these days because the capacity on amperes change when the voltage changes, but the watts or the watt hours don't change, 1000 watt hour is 1000 watt hour doesn't matter how you wire your system, 12 volts or 120 volts. so if you use the watt hours to measure your system you will not confuse by the amperes.

[Lacosteiq]

The power company and the electrical professionals using Watts or watt hours to record the consumption and capacity. They don't use amperes these days because the capacity on amperes change when the voltage changes, but the watts or the watt hours don't change, 1000 watt hour is 1000 watt hour doesn't matter how you wire your system, 12 volts or 120 volts. so if you use the watt hours to measure your system you will not confuse by the amperes.

My friend i do not know how to thank you i understand now what that mean i will chose the right type and capacity on my little experience i take from you


My regards for you and your family

[paulcheung]

You are welcome, cheers.

[Lacosteiq]

You are welcome, cheers.

My friend

Today i found two type of battery 12v 200ah

1- dry cell type
2- wet cell type

This two type i found in car accessories market and the price is fair 150$ for each one i think its for car use can i use one of them i will make
3 string 4/pc 12v 200ah so in total i will have 48v 600AH what you think i ask a lot for the flooded type they told me its the same of wet cell type because we use acid to fill the battery i need your advise my friend before i buy them .


Yours

Hussein

[paulcheung]

What you need is true deep cycle FLA batteries, not car SLI batteries. at least get the hybrid golf cart battery. I don't know what kind battery is the 200 ah battery, Can you give the name and model number? Can it be seen on the internet? if is SLI battery it will last no time, so the choice is yours, the best one would be the 6 volts 380 ah deep cycle battery, if you can't get or don't want them, just get what you can get, when it dies, you have to just replace them.

Cheers.

[Lacosteiq]

What you need is true deep cycle FLA batteries, not car SLI batteries. at least get the hybrid golf cart battery. I don't know what kind battery is the 200 ah battery, Can you give the name and model number? Can it be seen on the internet? if is SLI battery it will last no time, so the choice is yours, the best one would be the 6 volts 380 ah deep cycle battery, if you can't get or don't want them, just get what you can get, when it dies, you have to just replace them.

Cheers.

Dear

I contact the dealer for flooded type he give me this link for battery its from china you can check it

http://upsml.en.alibaba.com/product/...time&edm_ver=e


Please check if its ok i will order


Regards

Hussein

[mapmaker]

To discharge 50 amps in one hour on 250AH batteries, that is 5C discharge rate

That is not correct. A 5C discharge rate would melt something. --mapmaker

[inetdog]

That is not correct. A 5C discharge rate would melt something. --mapmaker

Gee, so picky. 5C, C/5 they seem pretty much the same to me.

[paulcheung]

Dear

I contact the dealer for flooded type he give me this link for battery its from china you can check it

http://upsml.en.alibaba.com/product/...time&edm_ver=e


Please check if its ok i will order


Regards

Hussein

You could try them, I don't know these batteries, they seems like AGM, if the quality is good, they will do the job.

[paulcheung]

That is not correct. A 5C discharge rate would melt something. --mapmaker

Oop, I don't know how the C get behind the 5, it should be C5 rate, thanks for point it out.

[Lacosteiq]

You could try them, I don't know these batteries, they seems like AGM, if the quality is good, they will do the job.

Dear

Thanks i will try these battery the problem is i do not see flooded type and no battery written on it flooded its all the same writen deep cycle battery i will try the battery that you see it will deliver in 45 days .


My regards

[inetdog]

Oop, I don't know how the C get behind the 5, it should be C5 rate, thanks for point it out.

Try again one more time, please:

C5, also more clearly written C₅, refers to the AH capacity at the 5 hour rate. What we usually mean when we use just C is the 20 hour rate capacity, C₂₀.
What you are talking about is one fifth of the capacity at the 20 hour rate, most clearly written as C₂₀/5. The "/" is critical.
The regulars know what you meant to write, but the newbies are likely to get confused.