EPEVER MPPT Solar Charge Controller 40A wattage

WIguy

New Member
I'm very confused on the total wattage capability the EPEVER MPPT Solar Charge Controller 40A can handle. On Amazon it says this on the upper description:

  • This 40 amp MPPT Solar Panel Charger works with 600W Solar Panel on 12V Battery System and 1200W on 24V Battery. Max Solar Panel 1560W, multiple load mode allow you set the load on/off in different situation. A Solid State Relay is recommended if you are using a Power Inverter
But below it says:

Technical Data

40A MPPT Charge Controller Nominal System Voltage: 12V, 24V

Rated Charge Current: 40A

Rated Load Current: 20A

Max PV Open Circuit Voltage: 150V / 138V

Max PV Input Power: 520W (12v battery) / 1040W (24v battery)

So what can the EPEVER MPPT Solar Charge Controller 40A handle, 1560w or 520w? I'm reading in the comments where people are connecting way over 600w?? I just need to know if I can safely connect my two 310w (37.2x x 8.34a) to this voltage controller? Thanks for any help!!!!!!
 

wiseacre

Solar Enthusiast
what is your system/battery voltage, 12 or 24?
if it's s 12v you're limited to 520w
with a 24v battery/system you can use the 1040w figure

Using two panels on a 12v system is questionable at best, you'd be way over the 520 watt limit

on a 24v system you can use both panels, in series or parallel with plenty of leeway of the charger's limits (volts, amps and watts)

edit:
I stand corrected. You can use both panels at 12v. (See Bud Martin's comment below)
 
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Bud Martin

Photon Sorcerer

For 12V you can over panel up to 3X the rating, that is why it shows 520W/12V, and MAX array of 1560W/12V, you will be fine with 620W of panels since it allows you to over panel up to 1560W for 12V system, I doubt that any one will want to install 1560W of panels only to use only 520W of power.
From user manual:
"This MPPT controller has a limiting function of charging current, the charging current will be limited within rated range, therefore, the controller will charge the battery with the rated charging power even if the input power at the PV exceeds."

"When the PV array straight polarity, the actual operation of the PV array must NOT 10 exceed three times of rated charge power."
 

JoeHam

Photon Sorcerer
What Bob said.......

And a simple version is that you MUST NOT exceed the max voltage for the MPPT or it will die.

It can burn off extra amperage as heat to some extent but cannot handle extra voltage.
 

pollenface

Solar Addict
It doesn't burn it off, it uses what it needs to produce up to it's rated output (clipping). The MPPT controls the pv array, not the other way around (unlike a PWM diversion controller like the Xantrex C35/40/60)

Epever specify a max pv array size 1.5x the rated output (780/1560w in 12/24v for 40a). Whether that's an arbitrary figure or not like 132% generally is for grid tied inverters, I don't know. Maybe one day I'll have the chance to hook 2kw of pv up to my 2210AN in 12v to see if it blows up.
 
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DerpsyDoodler

Photon Sorcerer
I'm very confused on the total wattage capability the EPEVER MPPT Solar Charge Controller 40A can handle. On Amazon it says this on the upper description:

  • This 40 amp MPPT Solar Panel Charger works with 600W Solar Panel on 12V Battery System and 1200W on 24V Battery. Max Solar Panel 1560W, multiple load mode allow you set the load on/off in different situation. A Solid State Relay is recommended if you are using a Power Inverter
But below it says:

Technical Data

40A MPPT Charge Controller Nominal System Voltage: 12V, 24V

Rated Charge Current: 40A

Rated Load Current: 20A

Max PV Open Circuit Voltage: 150V / 138V

Max PV Input Power: 520W (12v battery) / 1040W (24v battery)

So what can the EPEVER MPPT Solar Charge Controller 40A handle, 1560w or 520w? I'm reading in the comments where people are connecting way over 600w?? I just need to know if I can safely connect my two 310w (37.2x x 8.34a) to this voltage controller? Thanks for any help!!!!!!
It will push a max of 40a. 40a @ 24v (24x40) = ???? watts. Now do the same calculation @ 12v.

Yes you can safely connect those 2 solar panels to it.
 

DerpsyDoodler

Photon Sorcerer
If the next question is "what does over-paneling mean?"

You can attach more watts in solar panels than the SCC will output at any given time. This means your charge curve (assuming perfect sun) will stay flatter across the top of the curve for a longer period of the day. So rather than only getting (for example) 40a during peak sun, you'll get 40amps for some time both before and after peak sun (increasing your overall production).

However, if you're planning to immediately fill it up (over-panel), you might as well just buy a larger controller to begin with. This way you get all of the peak production and not just what the controller can handle.

Over-paneling is good for something you plan to grow into or if you just can't afford to go with a larger controller to start.
 

WIguy

New Member
Thank you everyone for your replies!!!! So, I can over panel, but on an ideal sunny day anything over the max wattage of 520 would be wasted?
 

Bud Martin

Photon Sorcerer
Thank you everyone for your replies!!!! So, I can over panel, but on an ideal sunny day anything over the max wattage of 520 would be wasted?
No, the power is not wasted, the charge controller will pull the power as needed from the panels to charge the batteries up to the maximum the charger can output, I.E. your US home AC outlet can supply power up to 1800W, so if you plug in 100W into the socket, are you wasting 1700W of power? of course not..
You will notice that when over paneling you will collect more total Watt/hr per day than not over paneling, you should arrange the panels so they will collect the power as much as possible during the day.
 

WIguy

New Member
No, the power is not wasted, the charge controller will pull the power as needed from the panels to charge the batteries up to the maximum the charger can output, I.E. your US home AC outlet can supply power up to 1800W, so if you plug in 100W into the socket, are you wasting 1700W of power? of course not..
You will notice that when over paneling you will collect more total Watt/hr per day than not over paneling, you should arrange the panels so they will collect the power as much as possible during the day.
I understand all that, I guess I'm looking more at the fact that I invested in two 310w panels that ill never get 620w out of them at any given time. I mean "usuable" 620w.

Now I have to sell my 3 week old Renogy 30a because it can't handle the watts and invest in the EPever. Oh well, lesson learned.
 

Bud Martin

Photon Sorcerer
I understand all that, I guess I'm looking more at the fact that I invested in two 310w panels that ill never get 620w out of them at any given time. I mean "usuable" 620w.

Now I have to sell my 3 week old Renogy 30a because it can't handle the watts and invest in the EPever. Oh well, lesson learned.
Now you are saying you have Renogy 30A model? I do not see Renogy 30A being mention in this thread, I thought we are talking about EPEVER 40A unit.
 

WIguy

New Member
Now you are saying you have Renogy 30A model? I do not see Renogy 30A being mention in this thread, I thought we are talking about EPEVER 40A unit.
The Renogy is my current controller that I'll probably have to sell. There's no need to even mention it. I'm asking about the EPever BEFORE I buy it because I can't afford to make this mistake twice!! So yes, we are talking about the EPever to better educate me before I buy it. Make sense?
 

WIguy

New Member
If the next question is "what does over-paneling mean?"

You can attach more watts in solar panels than the SCC will output at any given time. This means your charge curve (assuming perfect sun) will stay flatter across the top of the curve for a longer period of the day. So rather than only getting (for example) 40a during peak sun, you'll get 40amps for some time both before and after peak sun (increasing your overall production).

However, if you're planning to immediately fill it up (over-panel), you might as well just buy a larger controller to begin with. This way you get all of the peak production and not just what the controller can handle.

Over-paneling is good for something you plan to grow into or if you just can't afford to go with a larger controller to start.
Is Amazon the best place to buy this EPever controller?
 

ForestCoCabin

New Member
I’m new to the EpEver 40amp controller and it’s frustrating that the display does not show WATTAGE for incoming power from the panels. I don’t see a way to change the display to WATTS in the manual. Am I wrong? Thanks
 

DerpsyDoodler

Photon Sorcerer
I’m new to the EpEver 40amp controller and it’s frustrating that the display does not show WATTAGE for incoming power from the panels. I don’t see a way to change the display to WATTS in the manual. Am I wrong? Thanks
if you already have the mt-50, it offers a plethora of information across various screens. in some cases you need to use the left <, right > arrows to go through the categories, then the up ^, down v arrows to browse through the screens of info (or vice versa, could be up/down then left/right). Referring to the manual is always a good place to start, though.
 

12VoltInstalls

Solar Addict
doesn't burn it off, it uses what it needs to… (clipping).
Someone just has to come up with a good analogy for electricity that divorces it from having mass and volume but I haven’t thought of one yet myself besides, “if you point a running water hose into a 5 gallon pail it will eventually just overflow and continue overflowing. If you point a hose with electrons running out of it into a 5 gallon pail, when it gets full the electrons just stop flowing” and even that’s not too good
 

DerpsyDoodler

Photon Sorcerer
Someone just has to come up with a good analogy for electricity that divorces it from having mass and volume but I haven’t thought of one yet myself besides, “if you point a running water hose into a 5 gallon pail it will eventually just overflow and continue overflowing. If you point a hose with electrons running out of it into a 5 gallon pail, when it gets full the electrons just stop flowing” and even that’s not too good
if you pointed a hose into a 5 gallon pail (which would be the equivalent of a capacitor) it would stop flowing once it's full. Presuming "full" is whatever voltage is being thrown at it. if i attach a 20v capacitor to a 12v circuit, the capacitor is full when it reaches 12 volts.

That said (and forgetting the capacitor analogy), if you were pointing a hose of electrons into a pail it will only flow if there is a complete circuit (somewhere for the electrons to flow out of). So, presumably, if there was a complete circuit, the bucket would never fill.

Search RSD Academy on youtube. That's where I've gained most of my electronics and electrical circuit knowledge.

Bob Duhamel is awesome. I believe DSL linked it on this forum; which is where i learned of it.
 
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