solar panel voltage to charge controller

[jerryallison]

am a newbie , i have 10, 24 volt 230 watt panels on my roof. not hooked up to cc at this time ..there wired in series of 2 , 5 sets parallel. i have a flexmax 80 cc still in box. my inverter is a aims pure sine 6000 watt , the battery bank are 8- GC2 6volt 230 ah,460 ah total in series of 4 = 24 volts and parallel ..my question?? outback cc good or 2500 watts , yet the nec national electric code says am ony good for 2000 watts , that being said! i have 2300 watts on my roof can only use 8 panels . 8x 230 watts = 1840 watts,, my inverter is 24 volts so i dont thing i should mess with the battery bank, the voltage off the panels is + or - 62 volts should i rewire my panels or hook them up to the cc as is and set the cc to 24volt .. am i ok???? please help

[Sunking]

am a newbie , i have 10, 24 volt 230 watt panels on my roof. not hooked up to cc at this time ..there wired in series of 2 , 5 sets parallel. i have a flexmax 80 cc still in box. my inverter is a aims pure sine 6000 watt , the battery bank are 8- GC2 6volt 230 ah,460 ah total in series of 4 = 24 volts and parallel ..my question?? outback cc good or 2500 watts , yet the nec national electric code says am ony good for 2000 watts , that being said! i have 2300 watts on my roof can only use 8 panels . 8x 230 watts = 1840 watts,, my inverter is 24 volts so i dont thing i should mess with the battery bank, the voltage off the panels is + or - 62 volts should i rewire my panels or hook them up to the cc as is and set the cc to 24volt .. am i ok???? please help

Just exactly how did you come to the conclusion the NEC limits your panel wattage to 2000 watts? NEC has a lot of requirements but panel wattage is not one of them.

Your real problem is your Panel Wattage > Battery > Inverter ratio is way outside of normal operating parameters. Based on your panel wattage and battery voltage the minimum battery capacity is 640 AH and max is 1000 AH. All you have is 460 AH being slammed with C/4 charge rate. With a 24 volt 460 AH battery the largest inverter they can support at full power is 1500 watts and you have 6000 watts. A 6000 watt 24 volt inverter needs a minimum battery capacity of 1900 AH and you only have 460 AH. You are playing with fire.

Not sure really what to tell you. Assuming you want to stick with 2400 watt panel input and 24 volt battery, you need to trade your golf cart batteries in for some real Deep Cycle batteries with a minimum capacity of 640 AH using 2 or 4 volt cells so you only have 1 single string and get the charge rate down to an acceptable C/8 charge rate. Next is get rid of that inverter. Assuming you upgrade the battery to 640 AH the largest inverter they can safely supply is 2000 watts.

In a properly designed system the inverter is no larger than the panel wattage under normal conditions, and that can only be done if the batteries are properly sized. Nothing you have is sized correctly.

[jerryallison]

ouch!

am planing on doubling my wattage by the end of the year 10 more panels of 4600 watts, that's why i bought the larger 6000 watt inverter, and expand my battery bank 5 sets of 4 ,220 ah total 20 batteries of 1100 ah ..that's why i bought the larger inverter..my house is 35oo square feet 5 bedroom all electric i use a average of 2700 kw a month ... the inverter is a grid tie 24 volt .... hurricane season coming i guess am not going to be ready...ouch!

[thastinger]

if you put all of the batteries in series to make a 48V single string you would be better off, but you wouldn't be able to use very many of those panels and keep the proper charge rate. If you're looking for hurricane backup power, you could run an EE fridge, small freezer and a few lights and a tv/radio for a few hours a day off of 5 or 6 of those panels, the battery bank you have now and the proper inverter (not the one you have).

I'd start by figuring out what you "have to have" working in a grid loss, then buy a Kill-A-Watt meter and figure out the daily Wh load of all the things you want available in a grid loss, then the folks here can help you design the system to work properly. In the end, I think you can sell some panels unless you want to spend 10K in batteries.