3s2p
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Bud Martin
Solar Wizard
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What is the full spec of the panels, especially the Voc?
What is the maximum PV input Voltage of Renogy SCC?
What is the maximum PV input Voltage of Renogy SCC?
Bud Martin
Solar Wizard
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OK, the max PV is 100V.
Panel #1 has 24.3V Voc, Imp 4.93A, 5.34A Isc.
Panel #2 has 22.3V Voc, 5.38A Imp, 5.86A Isc.
So you are safe to put 3 panels in series and still be below 100V limit even in cold weather.
The choices will be: the two strings will be connected in parallel.
1) Two strings: each string consists of one Renogy in series with two HQST in series.
2) Two strings: first string consists of two Renogy in series with one HQST, second string will be 3 HQST in series.
Have to do calculation as to which one will produce the most power, I need to do some math.
Panel #1 has 24.3V Voc, Imp 4.93A, 5.34A Isc.
Panel #2 has 22.3V Voc, 5.38A Imp, 5.86A Isc.
So you are safe to put 3 panels in series and still be below 100V limit even in cold weather.
The choices will be: the two strings will be connected in parallel.
1) Two strings: each string consists of one Renogy in series with two HQST in series.
2) Two strings: first string consists of two Renogy in series with one HQST, second string will be 3 HQST in series.
Have to do calculation as to which one will produce the most power, I need to do some math.
Last edited:
MisterSandals
Participation Medalist
22.3V + 24.3V x2 = 70.3V
70.3V x 4.93A = 346W per string
2x in parallel = 692W
22.3V x2 + 24.4V = 70V (gets clipped to 66.9V in parallel with other string)
22.3V x3 = 66.9V
66.9V x (4.93A + 5.38A) = 690W
you would never know the difference no matter how you wire them in 3S2P
It’s late…hopefully i did this right…I showed the math!
pollenface
Solar Addict
do you mean a diagram like this?
MisterSandals
Participation Medalist
No fair answering the question that the OP actually asked.
It’s late, I was distracted by numbers, the shiny bits.
pollenface
Solar Addict
I'm too drunk for numbers
chrisski
Solar Boondocker
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As much as I like that diagram, this will show a + and neg to a SCC:
The first hit takes you to this very good explanation:
How wiring in series vs parallel affects solar array amps & volts
The amps and volts of a solar panel array can be affected by how it is wired. This blog post will teach you everything you need to know about this.
www.explorist.life
3S2P has the advantage of being very simple to hookup. You just need a pair of MC4 Y-connectors. No extra fusing needs to be done. And the higher voltage will offer a little better low light charging than 2S3P.
2S3P will offer a little better shading performance than 3S2P if arranged properly for the shading patterns. But now you need a combiner box and each of the 3 strings needs to be fused.
Rednecktek
Solar Wizard
Plus your 3s/2p will be able to harvest power in lower light conditions such as early morning and late afternoon because the controller has more to work with.
4S2P could work but given the Voc of the panels you would need a SCC that can handle 120V or more input.
Also keep in mind that all panels in a given series string really should be in the same plane and you want to avoid any partial shading on a series string.
Also keep in mind that all panels in a given series string really should be in the same plane and you want to avoid any partial shading on a series string.
Bud Martin
Solar Wizard
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I was not so sure if the OP is asking for diagram on how to hook up un-match panel, or just want diagram of 3s2p.
But since OP ask the question I then suspect that OP may not know about the PV Input Voltage limit, that is why I ask about the spec of the panels and the SCC first.
But since OP ask the question I then suspect that OP may not know about the PV Input Voltage limit, that is why I ask about the spec of the panels and the SCC first.
pollenface
Solar Addict
That's a much better diagram than mine.
pollenface
Solar Addict
3s2p will be safer for your controller on cold mornings, staying 12v will be fine.
