I hope this is kosher, cause I made a post elsewhere bc I’ve got some questions…
But I found this thread after posting and you guys are SO CLOSE to helping me that I’m gonna post my questions here and post a link to my post.
Maybe y’all can help me out, TIA!
I have 6x 250w SanTan panels on the roof of my bus.
I have 2x EPEver BN 40a 150v MPPT.
I have 3S2P setup on panels, with 3 on each side of my bus that I can tilt, thus 2 MPPTs for voltage/sunlight differential, which I believe is necessary.
I have 15x 3.2v 400ah cells connected 3P5S for an 18v battery.
I am hoping to charge my battery bank with these EPEvers to ~18v.
Will I have to put the MPPTs into 24v charging mode?
Epever Manual shows 9-17v parameter -says “please use double value in 24v” charging, but will the MPPT recognize my battery as a 24v version if voltage runs from 15.5v-18v?)
OR in custom battery mode can I set these parameters to whatever I want between 8v-32v as stated elsewhere in manual without worrying abt “24v mode?”
What do y’all think of this setup anyway?
I’m wondering if I’m actually oversized on panels; I believe this 150v unit is rated for 780W of panels on 12v systems or 1560W on a 24v system, just wondering what this means for my setup.
Am I correct that the MPPT’s rated charge power of 520W (for 12v) is much lower than MPPT max PV rating of 780W, meaning I’m potentially leaving some current at the panels, but not leaving much bc panels are 5+ years old?
Can I safely assume these MPPTs will charge my batteries in full sun to 18v at 28.8a? Or is my math inaccurate?
Final question: is my 150v MPPT at risk of over-voltage from 3x ~40v panels in cold/sunny weather wired in series? I count just 120v max input but I can’t find precise values for how high the input might get in some conditions.
Panel sticker shown below for anyone interested.
Here is my original post if cluttering this post isn’t helpful:
Thread 'EPEver BN 40a MPPT Battery is 3S5P'
https://diysolarforum.com/threads/epever-bn-40a-mppt-battery-is-3s5p.36590/