Epever controller

[Majkhands]

Hello I have a 4215BN, 4 - 6v gcart batteries and 3 - 270w 39v 15a solar panels 3p. A 2000w inverter with two 120v. 1 showing 100v the other 110v

The Charge controller shows 40v but never above 3amps, full dun shade, clouds... 3 panels in parallel should be close to 30amps.

The panels are:
72 cell, polycrystalline
Specifications:
Rated Power: 270W
Open circuit voltage (VOC): 44.4 V
Max power voltage (VMP): 35.5 V
Short circuit current (ISC): 8.25 A
Max power current: 7.60 A
Power Tolerance 0/+3%
Maximum system voltage: 600V (UL)
Fuse Rating: 15 A
IP65 Junction Box w/MC4 Compatible Connectors
Frame: Anodized aluminum alloy
Weight: 61.7 lbs
Dimensions: 77 x 39.05 x 1.81 inch

The batteries are
Les Schwab GC2-6V,
105 min @ 75a (no clue what that means)
Marine deep cycle
Wired 2s2p

Would wiring it as 24v instead of 12v
One post I read here indicated the charge controller would output what the system called for so I ran the inverter heavy. It would not run s vacuum. My 110v LED lights were flickering.
Am I missing something or should I reasonably expect 750w at 35v would show more than 40v at 3 amps under load?

Thank you as always for all the insights.

 

[pollenface]

3 amps sounds about right for "full dun shade clouds"

 

[Majkhands]

I mispoke the panels are rated at 7.6a, I confused it with fuse rating. 3 wired in parallel should increase the amperage while the voltage remains the same. With that consideration 3 panels in full sun should produce more than 3 amps total, I think. The EP controller never shows above 3 amps. My understanding is the controller limits the power to the draw. With that in mind I added the inverter to pull more power while the batteries are at full charge. Still never above 3 amps says the controller.aybe a setting is not right. I did allowit to set defaults. Batteries connected to detect 12v then added the panels at 24v.

 

[sunshine_eggo]

2S2P means 12V system

40A means charging current, not panel current, thus 40A * 14V charge voltage = 560W total - never more.

Would wiring it as 24v instead of 12v

No. Your Vmp is well more than you need.

One post I read here indicated the charge controller would output what the system called for so I ran the inverter heavy. It would not run s vacuum. My 110v LED lights were flickering.

Vacuum has a heavy surge load, and your inverter probably can't handle it.

Am I missing something or should I reasonably expect 750w at 35v would show more than 40v at 3 amps under load?

Per above, you'll never get 750W out of your system. 40A is too low.

Another restriction on power is if your battery is nearly fully charged. To test this, apply a load > 500W and see how the panels perform.

 

[pollenface]

What is the voltage of your battery bank during the 3amp charging?

 

[Majkhands]

The battery voltage, as I remember is in the 13.5 to 15v range.
Here is what I think I know from what the meter says 12 volts x 3 amps is only 36 watts. A fraction of 1 panels output. I am wasting the capacity of the other 2 completely.
I do have a 4k/8k inverter at 12 volts. I expect even if I pull a limited load it may overwhelm the system. The magic may escape somewhere that will not be in a happy place.

 

[sunshine_eggo]

Hello I have a 4215BN, 4 - 6v gcart batteries and 3 - 270w 39v 15a solar panels 3p. A 2000w inverter with two 120v. 1 showing 100v the other 110v

I do have a 4k/8k inverter at 12 volts. I expect even if I pull a limited load it may overwhelm the system. The magic may escape somewhere that will not be in a happy place.

Which is it?

 

[Majkhands]

I have both the 2kw is wired in the 4kw is not. I am concerned it will overload the system as it stands.

 

[sunshine_eggo]

I have both the 2kw is wired in the 4kw is not. I am concerned it will overload the system as it stands.

4kW @ 12V is a big ask. 3kW is generally regarded as the upper limit due to the high current required.

What gauge cables are between the battery and inverter, and how long are they?

 

[12VoltInstalls]

Am I missing something or should I reasonably expect 750w at 35v would show more than 40v at 3 amps

You are missing something

battery voltage, as I remember is in the 13.5 to 15v range.

12.8-13.2V is FULL charge. You will get nothing more from the panels since there’s no load for it to go.

Here is what I think I know from what the meter says 12 volts x 3 amps is only 36 watts. A fraction of 1 panels output. I am wasting the capacity of the other 2 completely.

No. That is likely all it needs to “float” and that’s all it will do.

added the inverter to pull more power while the batteries are at full charge. Still never above 3 amps says the controller.aybe a setting is not right. I did allowit to set defaults. Batteries connected to detect 12v then added the panels at 24v.

Unless the batteries- which sound quite robust- go below their charge voltage which could take some time the SCC won’t give them more charge. It will stay in float.

Can you post a screenshot of your settings, please?

 

[Majkhands]

I have the cables that came with the inverters. Neither over 18" in length.
I will post screen shots when I return.
I guage the battery level based on the number of bars indicating battery charge. They remain at 2 bars out of 8 most of the time. At full sunlight they charge (8 bars) in a little under 2 hours at the limited volts/amps reported by the charge controller.
The limited load I put on them pulls them down while charging in 3 hours.

 

[sunshine_eggo]

I have the cables that came with the inverters. Neither over 18" in length.

Probably not adequate. Most aren't.

I will post screen shots when I return.

Please.

I guage the battery level based on the number of bars indicating battery charge. They remain at 2 bars out of 8 most of the time. At full sunlight they charge (8 bars) in a little under 2 hours at the limited volts/amps reported by the charge controller.

Unfortunately, that's voltage-based via an unknown relationship and likely not a good way to estimate charge.

Pics of your setup will definitely help.