Mickie
New Member
- Joined
- Feb 24, 2022
- Messages
- 213
I have 2 solar panels connected in series the specs are in the pics. How ever on my charge controller im seeing over 20amps. Why is the amprage that high?
Shouldnt the Amps stay at the max amp for 1 of the panels? Or am i not understanding correctly?W=VA
The watts incoming from the panels at a higher voltage will produce higher amps at battery voltage.
This explanation helpsPower in = power out
V_in * I_in = V_out * I_out
Since your panel voltage, V_in is higher than battery voltage, the battery current at battery voltage will be higher than the panel current.
At battery: 27.9V * 16.2A = 452W
which is really close to the 440-463W power reported by the MPPT.
Using your panel numbers:
2X Vmp = 70V
1X Imp = 9.79A
In a perfect situation, you would get 70*9.79 = 685W
685W at battery votlage would be, 685W / 28V = 24.5A
This explanation helps
Yea this is the reasoning i had in mind y i kept wondering why the amprage went up that high. Thanks for vlearing this up for me.Of you had a PWM controller, they work by shorting the panels to the battery, not by converting high voltage/low current to low voltage/high current. In this case you would not see current above panel specification UNLESS you had the two panels in parallel. In that case, you would see no more than 2X panel current.
That being said. I now have 2.5mm² wire running from my panels to charge controller. Would it be good to change from the 2.5 to 6mm²?
I will be expanding to a 2s2p array eventually.2.5 is just under 13 gauge and can just handle 10A, so you should be good; however there may be losses. 6 is closer to 10awg and can handle 30A. If you ever plan to expand the array or want to do a long run, 6 would be preferred.
Let's say your panels are at 480v @ 1 amp. That would be 48v @ 10 amps to the battery (less conversion loss).Shouldnt the Amps stay at the max amp for 1 of the panels? Or am i not understanding correctly?
I will be expanding to a 2s2p array eventually.
Yea i will be changing to 6mm² before i go 2s2p.With 2P, your panels could put out 20A. >3.31 would be needed. 6 would be better.