I have a 20a mppt controller, what if my amps exceed 20?

[goombah111]

Adding another panel and they should be right around 20a due to MPPT conversion(panels are 6a but extra volts convert to amps),

1. What if they peak at like 21a? What if it went to 30? Would it simply not output or would it fry the device?

2. Is the 20a rating for input or output? input will be about 11, output will slightly exceed 20 in full sun.

[sdold]

Adding another panel and they should be right around 20a due to MPPT conversion(panels are 6a but extra volts convert to amps),

1. What if they peak at like 21a? What if it went to 30? Would it simply not output or would it fry the device?

2. Is the 20a rating for input or output? input will be about 11, output will slightly exceed 20 in full sun.

MPPT controllers generally limit their current safely if "over paneled", and the amp rating is usually the output (into the battery). What's the make and model?

[SunEagle]

Yeah I am curious who makes a true 20amp MPPT CC. Usually they start at 30 amps.

[goombah111]

MPPT controllers generally limit their current safely if "over paneled", and the amp rating is usually the output (into the battery). What's the make and model?

Yeah I am curious who makes a true 20amp MPPT CC. Usually they start at 30 amps.

image.png

[SunEagle]

Ok that looks like a valid MPPT CC. You will have to check on the maximum input wattage to see if you will stay below it or go above. Most quality MPPT type CC will just clamp the input and only produce the stated amps going out. Others may release the magic smoke by being overloaded.

Remember your panel wattage is under ideal conditions. The true output of a panel wattage will depend on the amount of sun hitting it and the temperature of the panel.

[goombah111]

You will have to check on the maximum input wattage

Looks like 780w based on this with 520w max output if I'm reading correctly.


Comb26052021001248.jpg

i guess that answers my question assuming I know what I'm talking about

[goombah111]

New question, not sure if I should make a new thread. Anyway...

Is there a way to limit the output amps on an Epever Charge Controller?
My batteries are too weak to handle the amps my panel puts out, is there any way to limit the amperage until I upgrade my battery setup?

[SunEagle]

New question, not sure if I should make a new thread. Anyway...

Is there a way to limit the output amps on an Epever Charge Controller?
My batteries are too weak to handle the amps my panel puts out, is there any way to limit the amperage until I upgrade my battery setup?

Well a quality CC will automatically limit the charging amps based on it's programing. It should go through the 3 phases of charging (bulk, boost and float) ending with a float charge regardless of what the panels put into it.

[goombah111]

Well a quality CC will automatically limit the charging amps based on it's programing.

How does it know the batteries are too weak to handle such a fast charge?

another 'nother question. Can a 24v inverter handle an 8s Li ion pack? Sla max is 28.4v and 8s is 33.6v.
I have an 8s 75c LiPo pack. Can the 24v Epever charge this?

[SunEagle]

How does it know the batteries are too weak to handle such a fast charge?

another 'nother question. Can a 24v inverter handle an 8s Li ion pack? Sla max is 28.4v and 8s is 33.6v.
I have an 8s 75c LiPo pack. Can the 24v Epever charge this?

I will tell you that LiPo batteries require a different type of charger that will balance each of the cells. If you try to use a charger without a BMS then you run the risk of overcharging one or more of the cells which can cause a violent reaction.

As for the first question, a CC usually will not know if the battery Ah rating is much smaller then what it can send it. It should see that the voltage increases pretty fast and then throttle back the charging current so it does not exceed the what the battery can handle. Unfortunately sometimes the battery gets cooked because it is just too small to handle any charging current.

[goombah111]

I will tell you that LiPo batteries require a different type of charger that will balance each of the cells. If you try to use a charger without a BMS then you run the risk of overcharging one or more of the cells which can cause a violent reaction.

It has balance leads and I have a balance charger, no worries there. I found out that this inverter has overvoltage disconnect at 30.5v so it's not gonna work unfortunately.

It should see that the voltage increases pretty fast and then throttle back the charging current

I hope so and will give it a try. Maybe the manual will say something, gonna read it front to back. Thanks