A power converter comprising: input power terminal being connectable to an output power terminal of a first circuit breaker; a first output signal terminal connectable to a control input terminal of the first circuit breaker to provide a first output signal (TRIP); a second output signal terminal connectable to a control input terminal of a second circuit breaker, which is connected upstream to the first circuit breaker to provide a second output signal (FAULT); and a controller adapted to perform an input protection test by: switching the first output signal (TRIP) from a first value to a second value to open the first circuit breaker; measuring a voltage at the input power terminal as a function of time; setting a flag to a first flag value if the measured voltage falls below a predetermined value within a first predetermined time interval after the first output signal (TRIP) has been switched from the first value to the second value; setting the flag to a second flag value if the measured voltage does not fall below the predetermined value within the first predetermined time interval after the first output signal (TRIP) has been switched from the first value to the second value; and saving the flag in a memory, the controller being further adapted to: provide the second output signal (FAULT) to the second circuit breaker to cause the second circuit breaker to open to disconnect power from the first circuit breaker and the power converter when the input protection test has failed. input power terminal being connectable to an output power terminal of a first circuit breaker; a first output signal terminal connectable to a control input terminal of the first circuit breaker to provide a first output signal (TRIP); a second output signal terminal connectable to a control input terminal of a second circuit breaker, which is connected upstream to the first circuit breaker to provide a second output signal (FAULT); and a controller adapted to perform an input protection test by: switching the first output signal (TRIP) from a first value to a second value to open the first circuit breaker; measuring a voltage at the input power terminal as a function of time; setting a flag to a first flag value if the measured voltage falls below a predetermined value within a first predetermined time interval after the first output signal (TRIP) has been switched from the first value to the second value; setting the flag to a second flag value if the measured voltage does not fall below the predetermined value within the first predetermined time interval after the first output signal (TRIP) has been switched from the first value to the second value; and saving the flag in a memory, switching the first output signal (TRIP) from a first value to a second value to open the first circuit breaker; measuring a voltage at the input power terminal as a function of time; setting a flag to a first flag value if the measured voltage falls below a predetermined value within a first predetermined time interval after the first output signal (TRIP) has been switched from the first value to the second value; setting the flag to a second flag value if the measured voltage does not fall below the predetermined value within the first predetermined time interval after the first output signal (TRIP) has been switched from the first value to the second value; and saving the flag in a memory, provide the second output signal (FAULT) to the second circuit breaker to cause the second circuit breaker to open to disconnect power from the first circuit breaker and the power converter when the input protection test has failed.