A master-slave clock system was developed and marketed in 1886 by Charles D . Warner and operated as the Standard Electric Time Company.
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A "'master clock "'is a precision clock that provides timing signals to synchronise slave clocks as part of a clock network.
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Electrical contacts attached to the mechanism generated minute, half minute and sometimes one second electrical pulses which were fed to the slave clocks on pairs of wires.
24.
In telecommunication and horology, a "'slave clock "'is a clock that depends for its accuracy on another clock, a master clock.
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The master clock " ( bottom center ) ", controlled by a temperature-compensated mercury pendulum, is wired to slave clocks throughout the building.
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In particular, it was to transmit electric time signals to slave clocks and time balls, and to coordinate simultaneous astronomical or meteorological observations at multiple distant locations.
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These older styles of slave clocks either keep time by themselves, and are periodically corrected by the master clock, or require impulses from the master clock to advance.
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The master clock in this system required 24 volts DC to both wind the master clock and as a source of current to advance the hands of the slave clock.
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The slave clocks did not have complete clockworks but simply a mechanism that, when energized electrically from the master clock, would advance the clock hands one unit of time.
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The slave clock is set to run slightly slow, and the reset circuit for the gravity arm activates a pivoted arm that just engages with the tip of the blade spring.
