Reversing drum switches are designed to start and reverse motors by connecting them directly across the line. The devices can be used with squirrel cage motors; one phase motors designed for reversing service and series, shunt and compound DC motors. The applications should be such that across the line starting of the motors is not objectionable, unless other means is provided for limiting starting current and torque. class 2601 drum switches are field convertible from maintained to momentary operation.