In one simple inverter circuit, DC power is connected to a through the center tap of the primary winding. A switch is rapidly switched back and forth to allow current to flow back to the DC source following two alternate paths through one end of the primary and then the other. The alternation of the direction of current in the primary winding of the transformer produces (AC) in the sec.
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A 12 volt panel has maximum power at around 17 volts so will need a minimum of 2 in series in a 24 volt system. There is no technical disadvantage but larger domestic sized 24 volt panels are cost effective.
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