how many panels can I run thru this CC to charge 12 volt battery bank?

Re: how many panels can I run thru this CC to charge 12 volt battery bank?

Welcome to the forum.

Well there is a better charge controller for about the same money: the MidNite Classic Lite: http://www.solar-electric.com/misoclli.html
That's brand new, with a warranty, functions better than the Xantrex (or anything else, really) and can have the LCD display added later if you wish.

A 12 Volt system on a 60 Amp controller basically adds up to a max of about (60 * 12 / 0.77) 935 Watts. So you could use four of those 235 Watt panels (940 Watts) comfortably. (The MidNite can handle up to 80 Amps without difficulty, by the way.)

That's enough charge power for 600 Amp hours of battery, so what size are your 6 Volters? Golf cart 220's by any chance? It would be in the right neighbourhood for that (660 Amp hours).

You would probably be best configuring the panels either all in parallel (in which case each will need its own 10 Amp fuse) or plan for expanding to a 24 Volt system by wiring two parallel strings of two in series (no fuses required).

A bit about array configurations: http://forum.solar-electric.com/showthread.php?16241-Different-Panel-Configurations-on-an-MPPT-Controller
And another about battery configurations: http://forum.solar-electric.com/showthread.php?15989-Battery-System-Voltages-and-equivalent-power

Re: how many panels can I run thru this CC to charge 12 volt battery bank?

Things to consider for wiring panels in series:
Do you actually have a long wiring run between the array and charge controller? Measure the distance and then you can try some numbers in a V-drop calculator.
Charge controllers work more efficiently when the nominal array Voltage is close to the nominal battery Voltage. The greater the difference, the lower the efficiency. If possible, staying with the 2X factor works best: 12 Volt battery with a 24 Volt array, 24 Volt battery with a 48 Volt array, 48 Volt battery with a 96 Volt array.
The biggest concern is with Voc of the panels potentially exceeding the charge controller's maximum input limit. In this case the Voc is 37.1 and all six in series would be 222.6. This would only work on the Classic 250, and if the weather gets cold Voc could reach 289 and would shut even that down (hyperVoc function on Classics allows up to system Voltage above the rating, so 298 on a Classic 250 with a 48 Volt system). The Vmp would be 181.2, which is way above any battery system Voltage.

So let's see what options there are for those panels with 150 wire run and a 12 Volt system.
Best for conversion: all six panels in parallel. Array @ 30.2 Volts & 46.7 Amps. You'd need 4/0 wire. Out of the question.
Middle of the road: three strings of two in series. Array @ 60.4 Volts & 23.3 Amps. Would need about 4 AWG which is rather unmanageable.
Easiest without fuses: two parallel strings of three in series. Array @ 90.6 Volts & 15.56 Amps. 8 AWG gives about 2.5% Voltage drop. Voc is 112 and even in cold temps any good MPPT controller should handle it (max < 150). This is acceptable.
Highest Voltage: all six in series. Array @ 181.2 Volts and 7.78 Amps. About 14 AWG would do. Conversion efficiency will suffer several % drop.

Output of six 235 Watt panels is likely:
1410 Watts * 0.77 efficiency / 12 Volts = 90 Amps peak current. A MidNite Classic 150 is rated at 96 Amps on 12 Volts maximum.
1410 Watts * 4 hours good sun * 0.52 over-all efficiency = 2.9 kW hours AC per day.
900 Amp hour 12 Volt battery bank @ 25% DOD = 2.4 kW hours AC.

(Please note these are rough calculations, not precise.)

Personally I hate to see that much power being utilized on a 12 Volt system. The current involved is not easy to handle.

Re: how many panels can I run thru this CC to charge 12 volt battery bank?

ywhic wrote: »

This may work though the Calc for the Classic 150 says Excessive Wattage.. says upto 97.9 amps into that 12v battery bank after MPPT conversion from the 15.56 amps in..

This could be, however the Classic should be able to clip that extra power on the occasions it occurs.
On the whole I wouldn't be running that size array on a 12 Volt system anyway. Great for 24, though.

Re: how many panels can I run thru this CC to charge 12 volt battery bank?

A couple of thousand for an Outback inverter/charger.

But there are options, especially if you don't need the built-in charger.
NAWS inverter section: http://www.solar-electric.com/inverters.html