What does overdriving an MPPT solar controller do?

Overdriving an MPPT solar controller simply means that the charge current of the incoming solar array exceeds the charge controller's maximum charge output. All Enerdrive MPPT solar controllers, Enerdrive DC2DC chargers, and Morningstar MPPT solar controllers can have oversized solar arrays connected to them without any damage being done to the controller. This has the advantage of providing you with power availability throughout the day and helps you to generate power when conditions are less than ideal.

When overdriving an MPPT solar controller, you will still be limited by the maximum output of the unit. This means that when conditions are at their absolute peak, you will be generating more power than can be used and some will be wasted. This is rarely a problem however, because the conditions required for maximum solar power generation mean that there is only a small window during the day when you will generate power than can be used.

Enerdrive recommends a maximum overdrive of 20% of the recommended maximum solar wattage. For example, the Enerdrive 40A MPPT Solar Controller could have up to 720W of solar connected to the input despite have a maximum recommended input of 600W. This extra 120W of power availability would allow your solar controller to output at its maximum for a much larger portion of the day, as seen in the graph below.