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Engineering, 03.04.2020 00:41 hawleyemily

In the early days of ac motor development, machine designers had great difficulty controlling the core losses (hysteresis and eddy currents) in machines. They had not yet developed steels with low hysteresis, and were not making laminations as thin as the ones used today. To help control these losses, some early ac motors were run from a 16.67 Hz ac power supply, while some lighting systems were run from a separate 50 Hz ac power supply.

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