What wattage are the panels putting out?

[NwCali]

My new battery will be here next week, atm I'm using 2 12volt lead acids (nothing special). Today I finally put a real load on it and this is what the solar charge controller is putting out, which I assume might be about max. Its four 410 watt bifacials with open circuit voltage of 49 vdc and around 10 amps (9.65) and my vmp is 42.50 volts.

So, what wattage are my panels putting out?

With the new battery I also have a growatt 3,000 watt all in one coming in to replace this one, which will go elsewhere....

 

[MisterSandals]

So, what wattage are my panels putting out?

I see 65V from your array on the screenshot above. How do you have these wired? 2S2P?

I see its charging at 43.5A so guessing your charge voltage to be 28.8V, that would be 1252W for the array.

Are you panels on the ground or raised and angled to take advantage of the 2 surfaces? I only know this from reading, no experience with bi-facial panels. 1252W seems low for 4x 440W but it depends on many things.

 

[NwCali]

yes 2s2p

They are also very dusty atm.... 1252 watts isn't bad (so far).

yes their off the ground, and have slightly different dirrections to take advantage of morning/evening angles..

there 410 panels though, not 440.

Thanks

 

[Bob B]

Power = current times voltage P=IE

 

[NwCali]

1252W for the array

On the right it says 1.10 kw This is less than 1252 watts, right? I've not yet wrapped my head on the math to figure the wattage via their screen...

 

[NwCali]

Power = current times voltage P=IE

Bob, can you show the math in this instance, that will help me see what I'm missing, thanks....

 

[MisterSandals]

slightly different dirrections to take advantage of morning/evening angles..

We talk about this a lot and recommend this setup quite a bit. How does that work for you? I'd love to hear how much you extend your solar day. Also wonder how it works for solar production when it goes from morning, to both (or in-between?) and then evening. Looking to learn something here!

 

[NwCali]

We talk about this a lot and recommend this setup quite a bit. How does that work for you? I'd love to hear how much you extend your solar day. Also wonder how it works for solar production when it goes from morning, to both (or in-between?) and then evening. Looking to learn something here!

Well, its still being working on installation and everything... And having two auto 12vdc lead acids means I rarely try to push anything.... I just hooked up a water heater and decided to see if it worked or not and took the picture, as, its obviously working. I'll be sure to figure it out when I slow down and can spend the time to monitor it better (I'm sure the growwatt all in one will go a ways in doing this also).

 

[Bud Martin]

Since you know that the PV Voltage is 65VDC, if you have clamp on DCA meter to measure the input current on the PV wire to the SCC then you can calculate the input power to the SCC, due to buck converter efficiency and system loss, the estimate of around 1200W is probably close to what you are getting.

 

[Bob B]

Bob, can you show the math in this instance, that will help me see what I'm missing, thanks....

I don't know how to decipher that screen for sure .... but I think Mr Sandals interpreted it correctly ....except that I think it would be 43.5 amps at 25.4V ..... so, 43.5 X 25.4 = 1104.9

 

[MisterSandals]

On the right it says 1.10 kw This is less than 1252 watts, right?

Ah yea, my eyes glazed over a little because there were so many numbers that represented unlabeled things. 1.10kW is indeed 1100W. That's after it goes thru the SCC which may have 10-20% loss (guess).

So if this represents part of an array of 1640W, pointed in 2 directions, its doing pretty well. What part of the day was this?

 

[NwCali]

I'd imagine at around 3pm or so, North West CA (almost oregon on the coast).

I'll get the math down tomorrow.

 

[NwCali]

Ok, have to ask this now, since my display amperage (43.5)is over rated (38.6) why is my wattage not at/near rated? I thought they would have some correlation.

 

[Bud Martin]

Ok, have to ask this now, since my display amperage (43.5)is over rated (38.6) why is my wattage not at/near rated? I thought they would have some correlation.

Can you please clarify about the 38.6 figure?
Do you have clamp on DCA meter to check the battery charging current to see if it matches the MT50 display?

 

[MisterSandals]

Ok, have to ask this now, since my display amperage (43.5)is over rated (38.6) why is my wattage not at/near rated? I thought they would have some correlation.

410 watt bifacials with open circuit voltage of 49 vdc and around 10 amps (9.65) and my vmp is 42.50 volts.

I see the problem.
If you have a 2S2P array, then your array is capable of producing 2x 42.5V and 2x 9.65A

Its the MPPT controller that turns the 19.3A at 85V (theoretical) into the charging voltage 25.6V at 43.5A.

So you have the amps from the array misunderstood. And, the MPPT in its mystical ways, converts that to charging voltage (that you set) and the max amount of amps.
The voltage and amperage of the array is manipulated by the SCC to where it determines it produced the most power (Maximum Power Point (tracking)).
This is why you see 67V input (but no display of amps from array). Must be about 1100W / 67V = 16.4A
Helpful?

 

[NwCali]

This is why you see 67V input (but no display of amps from array). Must be about 1100W / 67V = 16.4A

This makes sense to me.

So I am right assuming if it was the arrays amps being shown that the wattage would be higher then?

I do have a clamp on meter, but this would require me being there and turning on a high amp load with full sun. I'll try to set all this up today. But I also should wait until I cut a few limbs so I can check near noon, as they are slightly shaded before 1:30 from a few limbs....

I chose this MPPT charger back when no one had anything in stock and it has a high voltage range (170) and I considered going 3S on the panels.... Once I'm sure about the display I'll post it on Amazon to help others who might have also bought it and not understood what its actually showing you.

 

[Greendream]

On my Magnum PT100 (MPPT) SCC it always pushes a lot more amps than my PV array puts out. I was confused about this in the beginning as I had a breaker trip at about 70A reading on the PT100. After a lot of testing (DC clamp meter on all strings and then on the home run at the PV combiner and also at the SCC). In the end all my confusion was based on a faulty breaker that tripped prematurely? Either way, once I used the clamp meter and posted the question/issue on our forum, it was determined that the MPPT SCC's "magic" as has been mentioned sends real good current to our batteries (my 48v batteries recommend 50-100A current to charge) but my array is only rated for about 54A max (25pc 195W mono - 5S5P). I haven't seen with a meter more than about 10.5A per string x 5 strings, I know it's within the rated current on my 63A breaker at the combiner box. I've hit about 73A from the PT100!