Abridgment of new trends in mercury arc rectifier developments

Research investigations conducted by engineers as well as physicists during the last few years have resulted in notable improvements in the mercury arc rectifier, in particular with reference to backfire protection and voltage regulation as well as improved manufacturing methods. These improvements have made it possible to build rectifiers of very large current capacities as well as for very high voltages. In order to explain the results obtained with the aid of these improvements the basic principle of rectification is briefly reviewed. Methods of testing rectifiers have also been improved upon and new ones developed. Standard parts are now used for different rectifiers up to the largest capacities. An account is given of notable recent rectifier installations for city subway service, for a portable street-railway substation, radio transmission, electrolytic zinc refining, and for Edison systems.