Electric clock

[3] It was powered with dry piles, a high voltage battery with extremely long life but the disadvantage of its electrical properties varying with the weather.

[5] In 1815, Giuseppe Zamboni of Verona invented and showed another electrostatic clock run with dry pile batteries and an oscillating orb.

Numerous people were intent on inventing the electric clock with electromechanical and electromagnetic designs around the year 1840, such as Wheatstone, Steinheil, Hipp, Breguet, and Garnier, both in Europe and America.

Matthäus Hipp, clockmaker born in Germany, is credited with establishing the production series, mass marketable electric clock.

In 1918, Henry Ellis Warren invented the first synchronous electric clock in Ashland, MA, which kept time from the oscillations of the power grid.

Near the end of the nineteenth century, the availability of the dry cell battery made it practical to use electric power in clocks.

These systems are found in locations where multiple clocks would be used such as learning institutions, businesses, factories, transportation networks, banks, offices and government facilities.

It consists of a small AC synchronous motor, which turns the clock's hands through a reduction gear train.

Thus the synchronous clock can be regarded as not so much a timekeeper as a mechanical counter, whose hands display a running count of the number of cycles of alternating current.

[10] However most electric clocks have rotors with more magnetic poles (teeth), consequently rotating at a smaller submultiple of line frequency.

[11] The accuracy of synchronous clocks depends on how close electric utilities keep the frequency of their current to the nominal value of 50 or 60 hertz.

[12] For example, European utilities control the frequency of their grid once a day to make the total number of cycles in 24 hours correct.

In 2011, the North American Electric Reliability Corporation (NERC),[14] a consensus-based industry organization, petitioned the Federal Energy Regulatory Commission (FERC)[15] to eliminate the TEC.

If the FERC adopts the NAESB petition, TECs will no longer be utilized in the United States and Canada, and clocks timed by them will likely wander uncontrolled until manually reset, however as of 2021 WEQ-006 was still in place.

Naval Observatory that, had TECs not been inserted in 2016, there would have been over seven minutes lost by electrically timed clocks over much of the United States and Canada, as shown in Figure 8 of their paper.

Telechron synchronous electric clock manufactured around 1940. By 1940, the synchronous clock became the most common type of clock in the United States
Electromechanical self-winding clock movement from Switzerland .
One of Alexander Bain's early electromagnetic clocks, from the 1840s
Gents' of Leicester Pulsynetic, C40A, Waiting Train, Turret Clock (1940s/50?). Photographed in the Ministers' Building (The Secretariat), Yangon .
photograph of Master Clock
Master clock from synchronized school clock system. c.1928 Electromechanical movement winds each minute and impulses slave clocks each minute. Operates on 24 Volts DC
Early French electromagnetic clock
Clock radio with synchronous clock, from the 1950s
The over 7-minute time error that would have developed in electric clocks over much of N. America had they not been reset after the March 2016 switch to Daylight Saving Time, and had TEC's not been utilized [ 12 ]