Why are panels on Amazon advertised as 12V when the VOC is 23V

[k490]

Hello was wondering why so many panels on Amazon are advertised as 12V when the open circuit voltage is 23V and Optimum Operating Voltage is 20.3V on these panels.

 

[chrisski]

They work well with a 12 volt PWM controller. They are not designed to hook to a 12 volt battery. I don't think you could find a solar panel capabble of hooking to a battery without a Charge Controller between them.

Seeing panels advertised as 12 volts or 24 votls is kind of misleading.

 

[Mattb4]

Enough voltage to charge a 12v battery and not enough to charge a 24v battery.

Not too many 16v batteries running around.

Amazon.com : 16 volt battery

 

[k490]

I'm using a MPPT controller has 100V max input. I was just wondering if there was something I missed with these panels.

 

[Mattb4]

With the 100v max input you would want to limit the number of panels in series to about 3 at the 23Voc level. Going to 4 would put you at 92Voc which could mean exceeding 100v if conditions were right.

ETA: 3 of the panels in series might not provide enough voltage to charge a 48v battery. Though it would be adequate for one of those 15 cell types.

 

[k490]

With the 100v max input you would want to limit the number of panels in series to about 3 at the 23Voc level. Going to 4 would put you at 92Voc which could mean exceeding 100v if conditions were right.

ETA: 3 of the panels in series might not provide enough voltage to charge a 48v battery. Though it would be adequate for one of those 15 cell types.

I'm not using those panels I bought two 265 watt VOC 38.5V Isc of 8.26 amps Qcell panels they are used from a solar installer here in Arizona just need to pick them up. I will be using the pair in series should have 20 volts buffer. If I want to add a 3rd panel have to wire it in parallel with those two trying to keep the amps below 10 amps total. The controller I have is a Renogy Rover 20 amp well see how it works kind of a cheap controller. This is in a shed just for fun really playing around learning how solar works right now it's only powering a 18W 110V LED strip light though an old 400Watt inverter. I had purchased a interstate 24DC deep cycle it functioned more like a starter battery returned it to costco. I bought a cheap amazon LifeP04 100ah 12v battery. I know it's not the best battery but I feel it's better then a deep cycle which is almost $200 now days. Big box stores no longer sell true deep cycles only these DC type which are duel propose are nothing more then starter battery rebranded.