A method and a control system for starting a motor (19), in particular a motor (19) for driving a compressor. The rotational speed (24) of the motor (19) is measured and compared to a minimum value. In the case that .omega..sub.motor (24) is smaller than the minimum value after a predefined time interval has lapsed, the motor (19) is stopped, and the maximum current level to be supplied by the power source (18) is changed, preferably increased, before a new attempt to start the motor (19) is initiated. Preferably, the voltage (22) supplied to an electronic unit (21) is also measured, and in the case that it drops below a minimum voltage level, the motor (19) is stopped, and the maximum current level is changed, preferably decreased, before a new start attempt is initiated. It is possible to adjust the supplied current level in such a way that power is conserved while sufficient lubricated of the moving parts of the compressor is ensured.