Do i need more solar panels?

[focuslinks]

Good day everyone,
Am new here.
I have a 2400watts 24v hybrid system
2 300watt solar panels
2 130AH batteries

Specs:
Inverter:

SOLAR CHARGER & AC CHARGER
Solar Charger Type	MPPT
Maximum PV Array Open Circuit Voltage​	102 VDC​
Maximum PV Array Power​	1000 W​
MPPT Range @ Operating Voltage​	30 VDC ~80 VDC​
Maximum Solar Charge Current​	40 A​
Maximum AC Charge Current​	25 A​
Maximum Charge Current	60 A

Solar panel:
2 pieces in series connection


Batteries:
2 12v 130AH Gel Battery

All connected and working.
The first day i installed the system it works fine, my total load was 250 - 300watts 5 - 8A, during the day but night 100 - 130watts 1- 2A, according to the inverter display and lasted for up to 12 hours, 18:00 - 06:00.

By default the system was setup to shut down or switch to the grid when the battery voltage is below 24.2v.
Since then the battery don't charge.
At noon the solar panels generate 62v 7-8A according to the the system displays.

anytime the load is above 250 watts the inverter will prompt low battery sign. And the battery voltage wont increase.

Please what am i doing wrong?

Or is the battery bad?
Or i need another solar panels?

Your assistance will be appreciated

 

[Quattrohead]

New or used batteries ?
Do you know how many watts the panels are actually producing ?

 

[focuslinks]

New or used batteries ?
Do you know how many watts the panels are actually producing ?

The battery is brand new

At noon the panel produces over 200 watts, 8 -10A, over 65v according to the inverter display, its doesn't stable

 

[sunshine_eggo]

Important that both 12V batteries show the same voltage when the 24V battery is at its peak. If either 12V is charged higher than specification, it will be damaged.

Were both 12V fully charged individually as 12V before putting in series for 24V?
Are you using thick cable - at least 2awg?
Are all connections properly torqued and of high quality?

 

[focuslinks]

Were both 12V fully charged individually as 12V before putting in series for 24V?
Are you using thick cable - at least 2awg?
Are all connections properly torqued and of high quality?

No i don't charge individual, i just connect the battery together, the connection is properly connected with high quality, battery connected with 4awg as recommended by the inverter manual

 

[focuslinks]

Can the solar arrays charge the battery?

 

[sunshine_eggo]

No i don't charge individual, i just connect the battery together,

This may be a problem. What is your charge voltage? When the inverter is displaying that voltage, what do each of the 12V measure?

the connection is properly connected with high quality, battery connected with 4awg as recommended by the inverter manual

4awg is too thin for a 2400W inverter @ 24V.

2400W/24V/.85 = 118A
Most 4awg can't handle that.

If you're not using anything near 2400W, it's not an issue, but it will be a limit if you use more power.

130Ah * 24V = 3120Wh - half of which is usable if these are lead acid batteries. If you use more than 50%, you will shorten their life very quickly.

Can the solar arrays charge the battery?

I would assume yes. Are they not?

 

[rodrick]

do you have a multimeter to check battery voltage
what is the output voltage of the inverter
what is hooked up to the battery directly
you only have about 65 usable amps of battery with this system possibly not enough storage

 

[MisterSandals]

Can you post a couple pics of your battery and inverter wiring?

What charge controller do you have and what are the charge settings? (Pic of charge settings)

 

[12VoltInstalls]

4awg as recommended by the inverter manual

I feel like that is too small for my preferences. If the chart says 4ga is right for 200A I guess it’s safe but I’d go bigger.

Can the solar arrays charge the battery?

2 12v 130AH Gel Battery

That will charge the batteries, but I think you don’t have enough batteries being they are lead acid.

anytime the load is above 250 watts the inverter will prompt low battery sign. And the battery voltage wont increase.

Please what am i doing wrong?

Cable throughput could be bottlenecking amps. Plus you should charge them @12V for 24hrs, disconnect and rest them a few hours, and verify balanced voltage as suggested.

 

[focuslinks]

What charge controller do you have and what are the charge settings? (Pic of charge settings)

The inverter is an hybrid inverter, the spec is posted above

 

[MisterSandals]

The inverter is an hybrid inverter, the spec is posted above

Not sure why your inverter is such a closely guarded secret. The specs tell nothing of the charge profile (how high it charges, whether there are multiple charge stages, termination current…).

 

[Rednecktek]

So some rough napkin math here but I think I see your issue.

130ah @ 24v = 3120wh ÷2 for lead = 1560 usable wh.

600w of solar panel × 4 hours of good sun = 2400wh max

250w average load × 24hr = 6000wh

Your panels can only generate about 1/3 of your total daily consumption. Even if we do this:

110w × 12hr = 1320wh daytime consumption means only 1/2 of your array generation can go towards recharging your batteries.

So you've got a couple problems that I see,

1: You've got 3kwh of load being supplied by 1500wh of battery, you need to either massively reduce your load or get more battery.

2: You're only getting about 1kwh net generation in perfect sun to recharge your battery. Without your loads that would probably be fine, but your loads really nerf things. Get more panels to be able to support your total sunlight hours load + fully charge the batteries. Another thing about lead acid is that the last 5% takes FFFOOORREEEVVEERRR so you're probably not getting fully charged before the sun goes down.

3: With the amount of charging deficiencies you may very well have done damage to your batteries by repeated deep discharges. A 24v LFP battery is about the same price as the same usable capacity as lead acid. If cold isn't an issue, consider replacing your battery with a LFP.

Ok, someone want to double check my napkin math please?

 

[focuslinks]

I feel like that is too small for my preferences. If the chart says 4ga is right for 200A I guess it’s safe but I’d go bigger.


That will charge the batteries, but I think you don’t have enough batteries being they are lead acid.

Cable throughput could be bottlenecking amps. Plus you should charge them @12V for 24hrs, disconnect and rest them a few hours, and verify balanced voltage as suggested.

Ok i do that as suggested

 

[Rednecktek]

2kw inverter, 24v system, 4awg is good for 125a regularly. Sounds about half the size it should be in my mind too.

 

[focuslinks]

Get more panels to be able to support your total sunlight hours load + fully charge the batteries.

Please like how many panels can i add, because the charger can only accommodate 1000watt, and maximum 102vdc? And i have initial 2* 300watt panels

 

[MisterSandals]

Please like how many panels can i add, because the charger can only accommodate 1000watt, and maximum 102vdc? And i have initial 2* 300watt panels

The maximum your SCC can utilize is 40A (according to pic of your specs).

So 40A x 28V charging = 1120W (max used by your SCC, everything over this will be clipped)

You can put 2 panels in series max to stay below the 102V input voltage (very critical not to be exceeded).
Then make 2 strings (4 panels total) and put in parallel with a Y connector (see link below), as a 2S2P array. This is a popular configuration and will work for you well.

https://www.amazon.com/BougeRV-Connectors-Branch-Parallel-Adapter/dp/B0753X68PS/

 

[12VoltInstalls]

Please like how many panels can i add, because the charger can only accommodate 1000watt, and maximum 102vdc? And i have initial 2* 300watt panels

So think of it like this: at midday optimal sun you will get max 40A charging. But at the early and late wings of the day, you will get much less than 40A output. So you can hedge that with more panels than max capacity in series-parallel by facing 1/2 the array SSE (145* or so) and the other half at 230* (SSW) and potentially get max output for more hours of the day and go much later in the day before the batteries need to pick up the loads.
Basically you overpanel to optimize the charging you need.

 

[focuslinks]

Howdy,

Here are what am getting from the system with the timestamp,

please is everything alright or the panel output is not accurate? e.g. The watt that am getting from the two panels I think am supposed to get more watt than what the system display. I have 2* 300watts but am getting up to 90watt early morning, even at the peak time all i get is above 250watts instead of above 500watts or something is wrong somewhere? The volts is accurate but am concerned about the watts. Please advise me on this, is it that the controller don't give the accurate watt readings?

 

[focuslinks]

So think of it like this: at midday optimal sun you will get max 40A charging. But at the early and late wings of the day, you will get much less than 40A output. So you can hedge that with more panels than max capacity in series-parallel by facing 1/2 the array SSE (145* or so) and the other half at 230* (SSW) and potentially get max output for more hours of the day and go much later in the day before the batteries need to pick up the loads.
Basically you overpanel to optimize the charging you need.

What about the maximum pv array power which is 1000watts