Four speed settings were possible, three provided by the main controller, and the fourth by a weak field flag switch. Shunt mode was used in depots and yards, and was achieved by connecting resistance banks in series with the motors. In series mode, the resistance was removed in steps, until the two motors were in series between the 600 V supply. The maximum speed in this mode was around . Parallel mode reconnected the motors in parallel across the supply, and allowed operation up to normal full speed. The weak field flag switch allowed higher speeds still, but was only to be operated on open sections of the line. Its operation was visible from outside of the train.