Other charging sources can be used in parallel with the Morningstar charge controller; you do not need to isolate the controller from the battery. For best performance when using other charging sources, ensure the charging source and Morningstar controller are set to charge to the same (or close) voltage. If the supplemental charging source is set to a higher charging voltage than the Morningstar controller, the Morningstar controller may go into a fault state temporarily when the battery voltage rises higher than the controller’s setpoint. The controller will automatically recover from this state when the battery voltage drops to a lower level.