I-14 (1913 to 1927), I-15 (1923 to 1927) Previous
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This model replaced the Types I, I-8, and I-10. The basic design of this meter (register and stator) introduced with this model carried over to all later models right up to the present (but not without improvements and changes along the way). This meter came in 3 different sizes, depending on the ampere rating (similar to the Duncan M2), and in all cases is a hollow iron casting with a rear cover accessible only when the front cover is removed. Unlike the I-8 and I-10 terminal covers, the I-14's terminal cover is captive (except on the 100A-300A versions) and swings out of the way when access is needed to the terminals. This meter was furnished with either a glass or a metal cover. In 1925 the magnet assembly was improved by adding a temperature compensator to keep the magnet strength constant over a wide range of temperatures, and these I-14s (and corresponding polyphase and switchboard versions) have the frame under the cover painted silver).

The I-14 was also offered for use on 25Hz circuits, and this version was split off in 1923 and renumbered the I-15. The biggest difference between the I-14 and I-15 was that it had a full-load speed of 16 2/3 RPM to the I-14's 33 1/3 RPM.

 
I-14, metal cover
David Dahle collection
I-14, glass cover
David Kingston collection
I-14, 100-amp
Seattle City Light collection