A fuel cell system is protected by monitoring at least one fuel cell parameter, comparing the parameter to a preset level, and disconnecting or reconnecting a main load in response to the fuel cell parameter. For example, a fuel cell system (300) is provided with a protection circuit (304, 308) that prevents operation of the fuel cells in the negative dP/dI region. System (300) includes a stack of fuel cells (302) connected in series and coupled to a main load (310). A controller (304) provides a control signal (314) based on the individual fuel cell voltage levels falling above or below a preset level. Control signal (314) is used to control a load switch (308) coupled between the stack of fuel cells (302) and the main load (310). The load switch (308) disconnects the main load (310) in order to prevent operation of the fuel cell cells in the negative dP/dI region.