Parameter AGM battery and Epever

[frankz66]

Hello everyone and thank you for accepting me. I am not very experienced in PV, I wanted to ask for some opinions from experienced users regarding my configuration:

2 180 watt 12v photovoltaic panels for one, so 360 watt totaili.

1 Epever 3210 AN

1 Electronicx 110 amp battery 12v c100 AGM

1 reverse green cell 12v/24v 500 watt max 1000 watt pure sine wave.

I find great doubts about the configuration of the software and asked as written before if I need to retouch some parameters as shown in the photo:

The battery manufacturer only provided me with some information about charging the battery, namely the boost to 14.40, the float at 13.62 (20 c°).

I just changed the equalization that should not be done on AGMs as they do not have the ability to "boil" ...

I set the compensation to -3 (but I don't know if it's correct) and the following values:

Float at 13.60 (to date unfortunately I have a temperature of 32 degrees)

Boost time at 30 mn

Equalization 0

110 the correct value of the battery

But do I know the other parameters, such as the discharge volts and how much?

I also use a constant load of 36 watts for 24 hours. In the morning I find myself with 12% of the battery!

 

[sunshine_eggo]

boost time to 120 minutes.

36 * 24 = 864Wh

+ whatever the inverter consumes (they use power just by being on). Let's say 5W.

That's another 5 * 24 = 120Wh

984Wh total used.

Were your panels in full sun facing due south and tilted properly for your latitude with no shading from dusk to dawn?

 

[frankz66]

boost time to 120 minutes.

36 * 24 = 864Wh

+ whatever the inverter consumes (they use power just by being on). Let's say 5W.

That's another 5 * 24 = 120Wh

984Wh total used.

Were your panels in full sun facing due south and tilted properly for your latitude with no shading from dusk to dawn?

Hi and thank you for replying. Yes the panels are tilted south and 30 degrees. I wonder if I increase to 180 mn? They advised me against increasing as it could overheat the battery. But I considered that if I have a 30 amp epever the panels that generate a maximum of 18 amps and the manufacturer recommended optimal charging 10 amps maximum 20 amps, is it worth increasing to 180? They told me that the faster the charge, the faster the consumption released will be, so it's good to recharge not too violently? If you saw the photo, what is the download parameter? Do you think the rest is correct? The battery is c100, could I always buy a different AGM one or not?

 

[sunshine_eggo]

360W/12V = 30A = the maximum current the MPPT can deliver to the batteries. The MPPT takes the higher voltage/lower current of the panels and sends lower voltage, higher current to the battery. Power_in = Power_out.

I missed the C100 rating. This means that the rating is only accurate for a consumption of 1.1A continuous. Most batteries are rated off a C20 rate. Charge rate is 10% of C20 rate (sometimes as high as 20%). A C100 battery with 110Ah is only about an 85Ah (4.25A) battery. This would put optimal charge current at 8.5 - 17A.

From here:

Caravan 110Ah C100.pdf

drive.google.com

If google translate is correct, they're recommending a 0.1-0.15C charge rate. Since no C20 rate is given, using C100, that's 11-16.5A. Pretty consistent with the C20 range.

Your 36W load is higher than 1.1A, so you'll never get 110Ah out of it. It's going to be closer to 85Ah.

Your battery will be full once you've attained 14.4V and held 14.4V until the current drops to 2A. You should adjust your boost time to whatever is needed to allow the current to drop to 2A while at 14.4V.

Note that the datasheet permits charging as high as 14.7V provided you are using temperature compensation. I would only do this if you actually have a temperature probe attached to the battery.

In most cases having some excess charge current isn't a problem because of how battery charging works and the intensity of the sun. You will only get 360W at high noon in perfect conditions. It will almost always be less - 70-80% of rated (about 270W). Additionally, once 14.4V is hit, the battery will not accept any more current than is necessary to hold 14.4V, so it's self-regulating at that point. In many cases, batteries are full or near fully charged by the time the sun is at max, and the battery won't accept high current.

I don't see "download parameter" and the rest of the settings are fine for now. It's important that you configure your boost time to be long enough to allow current to drop to 2A while the battery is held at 14.4V.

 

[frankz66]

360W/12V = 30A = the maximum current the MPPT can deliver to the batteries. The MPPT takes the higher voltage/lower current of the panels and sends lower voltage, higher current to the battery. Power_in = Power_out.

I missed the C100 rating. This means that the rating is only accurate for a consumption of 1.1A continuous. Most batteries are rated off a C20 rate. Charge rate is 10% of C20 rate (sometimes as high as 20%). A C100 battery with 110Ah is only about an 85Ah (4.25A) battery. This would put optimal charge current at 8.5 - 17A.

From here:

Caravan 110Ah C100.pdf

drive.google.com

If google translate is correct, they're recommending a 0.1-0.15C charge rate. Since no C20 rate is given, using C100, that's 11-16.5A. Pretty consistent with the C20 range.

Your 36W load is higher than 1.1A, so you'll never get 110Ah out of it. It's going to be closer to 85Ah.

Your battery will be full once you've attained 14.4V and held 14.4V until the current drops to 2A. You should adjust your boost time to whatever is needed to allow the current to drop to 2A while at 14.4V.

Note that the datasheet permits charging as high as 14.7V provided you are using temperature compensation. I would only do this if you actually have a temperature probe attached to the battery.

In most cases having some excess charge current isn't a problem because of how battery charging works and the intensity of the sun. You will only get 360W at high noon in perfect conditions. It will almost always be less - 70-80% of rated (about 270W). Additionally, once 14.4V is hit, the battery will not accept any more current than is necessary to hold 14.4V, so it's self-regulating at that point. In many cases, batteries are full or near fully charged by the time the sun is at max, and the battery won't accept high current.

I don't see "download parameter" and the rest of the settings are fine for now. It's important that you configure your boost time to be long enough to allow current to drop to 2A while the battery is held at 14.4V.

Thank you, you were the only one who gave me some very exhaustive answers !! I wanted to ask you about the solar panels where a maximum power of 9 amps is stated in the data sheet (see attachment). So from what you write, if I see 18 amps (once I read this value), will the actual amps that will go in battery be e.g. 18 amps at 16v panels, at 12v different value? I bought a 110 amp battery thinking of charging at least 80 watts for 12 hours (at night). I seem to understand that this battery is not good or always AGM what kind of battery should I buy to have c20-charged performance as you say? The longest duration time, refer to the boost time charging set at the moment at 120 mn? If yes, this value is at most 180 mn. Then recapitling: the 2 panels of 180 watts toatli 2 panels 360 watts, power 18 amps but at 12v Even though I've never seen this value on epever and if anything I'll see it? Because the software shows me that the battery enters e.g. power panel 14.5 amps battery 13 amps when you write to yourself that actually 12 v are more? If I have to change the battery that beats AGm do I have to buy and what features? Thanks again for the detailed answer!

 

[sunshine_eggo]

Thank you, you were the only one who gave me some very exhaustive answers !! I wanted to ask you about the solar panels where a maximum power of 9 amps is stated in the data sheet (see attachment). So from what you write, if I see 18 amps (once I read this value), will the actual amps that will go in battery be e.g. 18 amps at 16v panels, at 12v different value?

Yes.

Power_in = Power_out

Power = volts * amps

For one panel:

Power_in = Vmp * Imp = 19.1V * 9.43A = 180.1W

Power_out = Battery voltage * battery current.

since Power_out = Power_in, Power_out = 180.1W

180.1W = battery voltage * battery current.

If battery voltage is at 14.4V, current would be:

180.1W = 14.4V * current > current = 12.5A

If battery voltage is at 12V, current would be:

180.1W = 12V * current > current = 15A

I bought a 110 amp battery thinking of charging at least 80 watts for 12 hours (at night).

80W * 12h = 960Wh of total energy consumption

In this case, you would need 960Wh/12V = 80Ah of USABLE capacity. Usable capacity of lead-acid is 50%, so this says you need 160Ah @ C20.

Capacity check based on current:

80W/12V = 6.7A

6.7A * 20 hours (C20) = 133Ah C20 rating.

You choose the highest of the two methods above

I seem to understand that this battery is not good or always AGM what kind of battery should I buy to have c20-charged performance as you say? The longest duration time, refer to the boost time charging set at the moment at 120 mn? If yes, this value is at most 180 mn. Then recapitling: the 2 panels of 180 watts toatli 2 panels 360 watts, power 18 amps but at 12v Even though I've never seen this value on epever and if anything I'll see it? Because the software shows me that the battery enters e.g. power panel 14.5 amps battery 13 amps when you write to yourself that actually 12 v are more? If I have to change the battery that beats AGm do I have to buy and what features? Thanks again for the detailed answer!

I think we are now experiencing a language barrier. I don't want to guess at your meaning.

 

[frankz66]

Yes.

Power_in = Power_out

Power = volts * amps

For one panel:

Power_in = Vmp * Imp = 19.1V * 9.43A = 180.1W

Power_out = Battery voltage * battery current.

since Power_out = Power_in, Power_out = 180.1W

180.1W = battery voltage * battery current.

If battery voltage is at 14.4V, current would be:

180.1W = 14.4V * current > current = 12.5A

If battery voltage is at 12V, current would be:

180.1W = 12V * current > current = 15A



80W * 12h = 960Wh of total energy consumption

In this case, you would need 960Wh/12V = 80Ah of USABLE capacity. Usable capacity of lead-acid is 50%, so this says you need 160Ah @ C20.

Capacity check based on current:

80W/12V = 6.7A

6.7A * 20 hours (C20) = 133Ah C20 rating.

You choose the highest of the two methods above



I think we are now experiencing a language barrier. I don't want to guess at your meaning.

 

[frankz66]

Ok, if I bought a lifepo4 lithium battery with these panels and controller which battery would be paired to take advantage of everything I have?

 

[sunshine_eggo]

If I correctly calculated your usable capacity need of 80Ah, a single 100Ah 12V LFP battery would suffice as 80% of LFP is usable.

 

[frankz66]

If I correctly calculated your usable capacity need of 80Ah, a single 100Ah 12V LFP battery would suffice as 80% of LFP is usable.

Yes, it's true, but the costs are 3 times more! And regardless of the cost, I'm still inexperienced. I attach the photo of my plant:
In addition to photos is connected a notebook with battery and 4 cameras, for a constant consumption of about 35 watts, I can pull until the morning with a battery residue of 10%.

 

[chriscappuccio]

A half-decent LFP isn't 3x the cost of an AGM. Some of the $400 range 100Ah 12v LFPs are worth looking at, a similar AGM is maybe 1/2 the cost. If you don't have low temp charging issues, AmpereTime is good.

 

[frankz66]

A half-decent LFP isn't 3x the cost of an AGM. Some of the $400 range 100Ah 12v LFPs are worth looking at, a similar AGM is maybe 1/2 the cost. If you don't have low temp charging issues, AmpereTime is good.

Thank you, can you give me some advice on the brand ? I usually buy on amazon.

 

[chriscappuccio]

Was that 32F or 32C ? What's the low temp during the cold months?

 

[frankz66]

Was that 32F or 32C ? What's the low temp during the cold months?

Hello, I live in Italy / Sicily so the cold temperature or rather the lowest in winter and at most 10 degrees, unlike in summer average is 32 degrees

 

[chriscappuccio]

Ok, then you should totally be using an LFP battery. I don't know about Europe but if AmpereTime is available, buy it and re-tune your Epever to the LFP values.

 

[frankz66]

Ok, then you should totally be using an LFP battery. I don't know about Europe but if AmpereTime is available, buy it and re-tune your Epever to the LFP values.

 

[chriscappuccio]

Also if there's any chance that you will need more power in the future, go for 12v 200Ah

 

[frankz66]

Thank you for your intervention.

 

[frankz66]

If I correctly calculated your usable capacity need of 80Ah, a single 100Ah 12V LFP battery would suffice as 80% of LFP is usable.

Given the power of 360 W photovoltaic panels, should I change the battery and buy a c20 or c10 to have more power maybe from 120 Amps or do I leave this c100 and I am limited to the 26 watt load?