Models C and F switchboard (1909 to 1912) Up
The Model C was built self-contained in ratings from 100 to 3000 amps. The field coils were wound astatically from strip copper in ratings up to 600 amps. Higher ratings used copper castings for the field coils. In all other details, it was similar to the Model E DC meter. Because of the high full-load amperage rating of the C, a special feature was built into this model to make calibration easier: A second set of current coils rated for 10 amps was placed within a gap on each side of the main current coils.

The Model F meter was identical to the Model C except for the cover which was metal with a glass front. Unlike the Model C, it was only offered for circuits rated between 100 and 600 amperes.

Model C
Electrical Meterman's Handbook
Model F
unknown collection (photo found on Ebay)