Are my 60 cell panels 12 or 24 v

[chuckinnc]

I bought some 230w panels to build a higher capacity system for my hobby shop. The panel label says 60 cell, open circut voltage 37 volts and vmp 29.8 volts. I believe the panel is for a 24v system. My question is, the old panels I had were 36 cell for 12 volt system, so if these are for 24 volt system shouldn't they be 72 cell ( twice the cells for twice the voltage) or will the panel still work with 12v controller & battery.

[sensij]

Those would be considered 20 V panels, also called grid-tie panels. You'll probably need an MPPT controller to use them with batteries... voltage is too low for PWM in parallel at 24 V, and putting them in series will usually be out of the input voltage range of a PWM controller.

[Sunking]

I bought some 230w panels to build a higher capacity system for my hobby shop. The panel label says 60 cell, open circut voltage 37 volts and vmp 29.8 volts. I believe the panel is for a 24v system. My question is, the old panels I had were 36 cell for 12 volt system, so if these are for 24 volt system shouldn't they be 72 cell ( twice the cells for twice the voltage) or will the panel still work with 12v controller & battery.

12 volt panels are 36 cells, and 24 volt panels are 72 cells.

[Mike90250]

The 29V is too low to safely rely on charging a 24V bank, which may need +30V for full recharging. Put 2 panels in series with a MPPT controller and you would be OK