Here's a few possible makeups for 5 wire DC systems, plus detail drawing of a 3 wire DC Generator.
Discussion thread for this topic is existing in the General Discussion area under the name: Historical systems
5 Wire DC System, using two separate 2-wire DC Generators, with a balancing Grounded Conductor - acting as a "Floating Neutral". The Grounded Neutral is common to both Generator circuits by the Series-Parallel connection of the Resistors.
Similar to the system above, except using Batteries for the DC power source.
5 Wire DC Interconnected Systems, using two separate 3-wire DC Generators.
Grounded Neutral Conductor is common to both Generator circuits by physical common connection between "Upper" Genny's "-" lead and "Lower" Genny's "+" lead.
Voltages found at various points are listed on the left side of Schematic.
For simplicity, the Generators are shown with output voltages of 10/20 VDC. Also, only the Armature windings are shown.
Similar to the System above, except using Batteries for DC Power source.
Simple detail of a 3-wire DC Generator.
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