Before starting a dynamo, examine it carefully to see that the brushes, lubricators, etc., are in order. The machine may then be run at full speed for a short time, with the brushes off, to see that the bearings are in order. It should then be stopped and the brushes adjusted to their places on the commutator. The main switch may then be closed and the dynamo set running, the speed being increased until the volt meter or a pilot lamp shows that the correct voltage has been reached. Then, as the load comes on, the brushes may be shifted backwards or forwards, as may be accessary, for sparkless commutation.