Induction Coils, How to Make, Use, and Repair Them. / Including Ruhmkorff, Tesla, and Medical Coils, Roentgen Radiography, Etc. Etc.

by H. S. Norrie

Coils in Series.

Ruhmkorff coils can be connected in series, but it is not to be recommended. When it becomes necessary, however, the cores should be removed, and one long core inserted, extending through each primary. This will bring the time constants of each primary coil together and prevent the interference otherwise present. The primary coils and secondary coils are connected in series by assuming that they are but adjacent sections of one complete instrument. Of course, as the resistance of the primary is raised, the electromotive force of the battery must be raised also.