METHOD AND ARRANGEMENT FOR CONTROLLING A SOLAR POWERED PUMP

1 . A method of operating a pump in a pump system having a photovoltaic panel system, an inverter electrically connected to the photovoltaic panel system, and a motor driving the pump and electrically connected to an output of the inverter, the method comprising:

setting a voltage limit for the inverter;

monitoring voltage produced by the photovoltaic panel system;

operating the inverter for rotating of the motor when the voltage produced by the photovoltaic panel system is above the voltage limit; and

disabling use of the inverter when the voltage of the photovoltaic system is below the voltage limit.

2 . A method according to claim 1 , comprising:

setting a rotational speed limit;

monitoring a rotational speed of the motor connected to the output of the inverter; and

disabling the use of the inverter when the rotational speed of the motor is below the set rotational speed limit.

3 . A method according to claim 2 , comprising:

restarting of the inverter by checking whether the monitored voltage is above the set voltage limit;

starting operation of the inverter if the voltage is above the set limit; and

if the inverter is disabled due to dry run fault or due to low rotational speed, then starting the operation of the inverter after a settable time delay.

4 . A pump arrangement comprising:

a photovoltaic panel system;

an inverter electrically connected to the photovoltaic panel system;

a motor driving a pump and electrically connected to an output of the inverter;

means for setting a voltage limit for the inverter;

means for monitoring voltage produced by the photovoltaic panel system such that the inverter will be controlled to operate for rotating the motor when a voltage produced by the photovoltaic panel system is above the voltage limit; and

means for disabling use of the inverter when a voltage produced by the photovoltaic system is below the voltage limit.