Mppt voltage

[Bewsama]

Hello everyone
I have this mppt charge controller
on 12v system
What will happen if I connect 2 of this solar panel in serial


The voc will be 48.6
But the vmp is 39.5

My question when the mppt controller say pv input 0-40 that's mean i can only connect an array that max VOC is 40 or max VMP is 40?
And what is the difference between voc and vmp

 

[12VoltInstalls]

My question when the mppt controller say pv input 0-40 that's mean i can only connect an array that max VOC is 40 or max VMP is 40?

Can you screenshot the spec sheet of the mppt?

For most SCCs I’d interpret that sticker to mean your max voltage is 60 which is a hard limit where permanent failure will likely occur. So your VOC for 2S panels of 48.62 at like 72*F which may be ok at 0*F

The 30A would typically be the max amps it will ever output to the battery(ies).

Most SCCs would auto-sense a 12v or 24v battery system. But I have no idea the specs on your controller or how it behaves. If it was under US$125 I’m not sure it’s a good choice but the spec sheet will illuminate that.

 

[Bewsama]

Can you screenshot the spec sheet of the mppt?

For most SCCs I’d interpret that sticker to mean your max voltage is 60 which is a hard limit where permanent failure will likely occur. So your VOC for 2S panels of 48.62 at like 72*F which may be ok at 0*F

The 30A would typically be the max amps it will ever output to the battery(ies).

Most SCCs would auto-sense a 12v or 24v battery system. But I have no idea the specs on your controller or how it behaves. If it was under US$125 I’m not sure it’s a good choice but the spec sheet will illuminate that.

Is built in with this inverter its cheap i can tell

If i connected them in parallel what the wire diameter i need

 

[12VoltInstalls]

So that’s an inverter/charger/solar charge controller AIO kind of thing?
It appears to say 60V max.
It appears that two of those panels will work.
I would use 10AWG solar wire in series or parallel; 2S would be ~20A snd 10AWG is good for 30A assuming a somewhat short distance.

But you need fuses and some other stuff.
It would seem you need to start at the beginning. (I can’t find that SCC device by model#). You are asking good questions but it seems like you don’t have the essential knowledge you need to assemble these items safely. Start at the beginning: more info on the SCC device and how you intended to use it.

 

[littleharbor2]

Spec. sheet clearly states for a 12 volt system - Max Voc, 40 volts.

 

[12VoltInstalls]

Spec. sheet clearly states for a 12 volt system - Max Voc, 40 volts.

Next column over says 24V 60VOC.

Additionally (like with Epever) these ‘translated’ instructions say “max amps” but fail to clearly state that panel voltage can be 24V or higher or “over paneled” by watts but the max is actually the most it will output in amps at a given battery voltage, not necessarily a limit on panel amps. Just a hard VOC limit.

So one can assume and probably be right that things will work but that’s an unknown model/brand at this point with just a spec sheet that mentions “optional” things so I’m guessing really. Not even a wildhat guess, just a guess.

 

[TomC4306]

Spec. sheet clearly states for a 12 volt system - Max Voc, 40 volts.

+1.
Magic smoke

 

[12VoltInstalls]

+1.
Magic smoke

The spec sheet says 24V 60VOC in a different column. Did anyone besides me try to actually read that?

 

[TomC4306]

The original poster stated a 12 volt system...
Therefore 40 voc Max

 

[TomC4306]

I was answering the original question

 

[TomC4306]

And this math should have been resolved before any equipment was purchased

 

[12VoltInstalls]

The original poster stated a 12 volt system...
Therefore 40 voc Max

As I mentioned, the VOC is a factor of the SCC and not a factor of the battery volts. That’s true on most equipment but even Epever words that oddly in their manual.
Nevertheless, I’m running 12V batteries and my panels are ~88VOC. That may limit my harvest as I have a 50A SCC and the SCC supports 150 VOC.

What’s not expounded on in OP’s spec sheet is whether or not it can accept series panels like his and yet still charge appropriately at 12V without damaging itself.

I was answering the original question

My apologies. I was thinking of the later issue of series and VOC

 

[mikefitz]

Perhaps a PWM solar regulator?

Mike