Advice PLEASE! 2 @ 235 watt Hanwha 60 cell solar panels & 40A EPEVER Tracer 4210A CC

[texman38]

Whoa. Give some other folks a chance to chime in before you commit to anything. Or else be back here "well I thought this would work, but the shop is full of smoke now"....

First, everybody's loads always grow, and 12V systems are limited by the amount of power you can move through the cables to the internal wires in the inverter (that means most 12V inverters skimp on the inside wires)
I'd suggest wire the panels in Series (if the Voc spec x2 is under the Max input rated voltage of the Controller) and use a 24V battery bank. Start cheap with a couple of 12V "marine batteries" which would give you 24V @ 200ah ($200) Or 4800 watt hours, half of which are usable. Need more power ? You panels could support 4, 6V golf cart batteries wired in series, giving 24V @ 400ah ($400) 9,600 watt hours , 4,800 usable.

Sizing the inverter. It needs to be large enough to not overload on your heaviest load. But larger inverters consume more power at idle. So knowing what your loads are before you start buying stuff, becomes important.. Most energy star fridges consume about 1Kwh daily.... Little dorm fridges, consume as much, or more, made really cheaply, little insulation, higher losses.
Most fridges will require a 1,000w inverter (pure sine) to reliably start up.

Thanks Mike, so the golf cart batteries sounds good, i have some already that I'd like to pull from my golf cart and replace with new. So, 4 wired in series and a 1000watt pure sine 24volt inverter? does that sound right? Now, the panels wired in series you were saying could be a problem with my inverter?

[Mike90250]

PV panel Voc will be close to 80V Can your Charge controller input handle that ? nothing to do with inverter.

[texman38]

I'd suggest wire the panels in Series (if the Voc spec x2 is under the Max input rated voltage of the Controller)

Can you tell me whether or not based on my CC info whether i can hook my 2 panels to it in series like you were saying? The VOC of my panel(s) is 36.8 x 2 (panels) = 73.6V and My CC has the following info:

Max. PV open circuit voltage	100V(at minimum operating environment temperature) 92V(at 25℃ environment temperature)
MPP voltage range	VBAT+2V～ 72V

[texman38]

I also found the info posted below on my CC, so if thats the case, and these panels are 235 wats each, could this CC handle 4 panels? and if so what would be an appropriate/reasonably sized battery bank for 4 panels... if i used 6v golf cart batteries (since i'm getting ready to retire 8 6v batteries in my golf cart anyway) could i use 8 6v batteries in some combination to come up with 24 volts?
Max.PV input power: 12V/520W,24V/1024W
Battery voltage range: 9V~32V
Max.PV open circuit voltage: 100VDC

[texman38]

or have 2 battery banks... each with 4 6v batteries.... and maybe there's a way to switch back n forth to charge each bank with the same CC and 2 panels? is that something ppl do? or do they usually have everything wired in 1 bank?

[Mike90250]

Trying to swap between different aged battery banks is futile. Trust me, don't.

You need 4, 6v golf cart batteries, and they should all be fully charged before you try connecting them up in solar,
2 panels in series is below the controllers death voltage of 100V, unless your location gets really cold.
Yes you can add more panels. and more batteries, but I'd wait till later, get your feet wet first, then decide if you want to buy More

[littleharbor]

If you haven't already decided, skip any thoughts of 12 volt systems. Start at 24 volt. 12 volt will severely limit your options and cause you to have to scrap your 12 volt equipment when you want to expand. 24 volt will allow you to build a system double the size of a 12 volt system, twice the solar panels, twice the battery capacity.

[texman38]

Trying to swap between different aged battery banks is futile. Trust me, don't.

You need 4, 6v golf cart batteries, and they should all be fully charged before you try connecting them up in solar,
2 panels in series is below the controllers death voltage of 100V, unless your location gets really cold.
Yes you can add more panels. and more batteries, but I'd wait till later, get your feet wet first, then decide if you want to buy More

Thanks Mike! So, let me ask you this, since i'd like to use the used batteries in my golf cart for my battery bank, if i took the best 4 out of the 8, would that be ok? or do i need 4 new golf cart batteries to start with? what would be the problem(s) from using used somewhat tired batteries? thanks!

[Mike90250]

Then you need to get a 6V battery charger, charge each battery, let it set a day, and then measure and see if the voltage has sagged.
The ones that sag worst, are duds. Then you hook a load onto the battery, 100W for 2 hours, and that will show up any other bad cells. Battery University is a good place to get ideas on testing batteries.

[texman38]

Then you need to get a 6V battery charger, charge each battery, let it set a day, and then measure and see if the voltage has sagged.
The ones that sag worst, are duds. Then you hook a load onto the battery, 100W for 2 hours, and that will show up any other bad cells. Battery University is a good place to get ideas on testing batteries.

Thanks mike! So like 100watt light bulb for 2hrs and then check voltage again? Looking for drop again? Or if it can even sustain the load?

[SunEagle]

Thanks for the info... i wish I understood more about all this but i don't... so if you could explain it a bit better i would appreciate it... 400AH at 12 volt would be how many batteries and what type? any recommendations? would you suggest 12 volt? why not 24 volts? is 12 volts more versatile in terms of being able to run small things...

To build a safe and reliable 400Ah 12volt battery bank I would use either 2V or 4V batteries rated 400Ah each. You would need 6 x 2V or 3 x 4V wired in series. Forget about going with 12volt type wired in parallel.

While a 12v system may be easier to build a 24v system would be a better choice to keep the wire size between the battery and inverter smaller and the amps going through it lower..

[texman38]

To build a safe and reliable 400Ah 12volt battery bank I would use either 2V or 4V batteries rated 400Ah each. You would need 6 x 2V or 3 x 4V wired in series. Forget about going with 12volt type wired in parallel.

While a 12v system may be easier to build a 24v system would be a better choice to keep the wire size between the battery and inverter smaller and the amps going through it lower..

Thanks SunEagle!!! yes, 24v battery bank seems the way to go... I am trying to determine whether I can use the ones that are in my golf cart (take the 4 best out of 6) and use those to start with... being that they are older (2014) and have not been maintained very well I'm concerned that they will be a problem? what concerns should i have about using these older batteries, since you mentioned being "safe and reliable" thanks!!!

[texman38]

Whoa. Give some other folks a chance to chime in before you commit to anything. Or else be back here "well I thought this would work, but the shop is full of smoke now"....

First, everybody's loads always grow, and 12V systems are limited by the amount of power you can move through the cables to the internal wires in the inverter (that means most 12V inverters skimp on the inside wires)
I'd suggest wire the panels in Series (if the Voc spec x2 is under the Max input rated voltage of the Controller) and use a 24V battery bank. Start cheap with a couple of 12V "marine batteries" which would give you 24V @ 200ah ($200) Or 4800 watt hours, half of which are usable. Need more power ? You panels could support 4, 6V golf cart batteries wired in series, giving 24V @ 400ah ($400) 9,600 watt hours , 4,800 usable.

Sizing the inverter. It needs to be large enough to not overload on your heaviest load. But larger inverters consume more power at idle. So knowing what your loads are before you start buying stuff, becomes important.. Most energy star fridges consume about 1Kwh daily.... Little dorm fridges, consume as much, or more, made really cheaply, little insulation, higher losses.
Most fridges will require a 1,000w inverter (pure sine) to reliably start up.

you wrote, "You panels could support 4, 6V golf cart batteries wired in series, giving 24V @ 400ah ($400) 9,600 watt hours , 4,800 usable." golf car batteries are usually @ 200ah not 400ah, so does that throw off your calculation? also, i really need to talk to someone, i have to keep running back here, type and wait/hope someone can help anser... would you mind talking on the phone with me i really need a contact i can text or call... id appreciate it greatly!!!

[SunEagle]

Thanks SunEagle!!! yes, 24v battery bank seems the way to go... I am trying to determine whether I can use the ones that are in my golf cart (take the 4 best out of 6) and use those to start with... being that they are older (2014) and have not been maintained very well I'm concerned that they will be a problem? what concerns should i have about using these older batteries, since you mentioned being "safe and reliable" thanks!!!

Using old batteries for your first system is ok as long as you recognize they won't last very long due to age and number of cycles they have seen.

Now the problem I see is that while you can use 4 of those 6v batteries chances are they are rated around 220Ah which only gets you a 24v system way below 400Ah so your available daily watt hours would be maybe around 1300 at best for a short while.

When the first set dies they you can replace them with 400Ah batteries at probably 2V or 4V ratings.

[texman38]

Using old batteries for your first system is ok as long as you recognize they won't last very long due to age and number of cycles they have seen.

Now the problem I see is that while you can use 4 of those 6v batteries chances are they are rated around 220Ah which only gets you a 24v system way below 400Ah so your available daily watt hours would be maybe around 1300 at best for a short while.

When the first set dies they you can replace them with 400Ah batteries at probably 2V or 4V ratings.

the 400ah 6v batteries are monsters and usually over $200 each as i recall... i may just stay with golf cart type batteries since they are cheap and durable as someone else said, so its a reliable source of power that won't kill my wallet and won't make me cry if i screw it up somehow, $83 x 4 and i'm good to go for years... Thanks for your help SUNEAGLE, just what i needed to know!!!