Always running late? Take caution – a faulty electric clock could make your punctuality problems even worse.
According to a study conducted by researchers at the National Institute of Standards and Technology and the U.S. Naval Observatory, a change in federal energy regulations may interrupt the way appliances, including the clock plugged in next to your bed, tell time.
Traditionally, electric clocks keep time based on the nominal 60 hertz electric current that feeds them. However, power systems can accumulate significant phase error in operation, meaning those pulses of electric current aren’t always stable or precise. This can cause synchronous clocks to gain or lose seconds.
“In modern practice, the electric power industry monitors this time error, and once it reaches a threshold – 10 seconds in the Eastern U.S., 5 seconds in the West, and at operator discretion in most of Texas – a procedure called manual Time Error Correction is initiated to back it out,” wrote study authors Jonathan Hardis from the National Institute of Standards and Technology and Blair Fonville and Demetrios Matsakis from the U.S. Naval Observatory.
According to the researchers, an analysis of industry-supplied TEC records indicates that without them, synchronous clocks could have drifted by as much as 7 and a half minutes between the daylight-saving time switches of March 2016 and November 2016.
However, last year, the Federal Energy Regulatory Commission eliminated the regulation that requires power companies to immediately correct for any errors in frequency, in part due to the costs associated with maintaining such precision.
“After 100 years, the era of your power company providing a correct-time service may be coming to an end,” the researchers wrote.
The relationship between the grid and timekeeping
More than a century ago, on Feb. 5, 1917, Henry Warren filed for a U.S. patent on the first synchronous electric motor that could turn the gears and hands of a clock. The clocks, as well as the company that produced them, adopted the trademark name “Telechron.”
“Prior to the Telechron clock, there was no clock that used the frequency of the power system as a timing reference,” the researchers said.
While under development, the Telechron clocks hit the same snag that researchers caution could affect them today: 60 Hz electric power was not always exactly 60 Hz.
“As a time-keeper, the device was a failure. It was off as much as 10 or 15 minutes a day. But it was a success so far as checking the accuracy of alternations, or waves, was concerned,” Warren said regarding the clock.
To combat the issue, Warren developed another device: one that could compare power line frequency with a precision pendulum clock, known as a Type “A” Master Clock.
Boston Edison was the first electric company to adopt the Type “A” Master Clock as their frequency standard in 1916. By 1947, the master clocks regulated over 95 percent of electric lines in the country.
“As an unforeseen benefit, once different electric utilities had sufficiently synchronized generation, it became possible to form the first electric power grids,” according to the researchers.
Will this affect all clocks?
It’s important to note that not all timekeeping devices will be affected by the change in energy regulations.
For example, quartz crystal oscillators, utilized by clocks, watches and other appliances, are the world’s most widely used timekeeping technology and will not be impacted by the change.
“Today, there is diversity in the way consumer clocks maintain their time accuracy,” the researchers said.
Other devices that won’t be affected include digital televisions, which receive time data from broadcasters, and smartphones, which similarly pull time data from cell sites. Computers and other internet-connected devices receive their time from network servers.
“Nonetheless, many electric clocks in our homes and offices – standalone, and integrated into appliances and time-sensitive devices (e.g., event recorders, lawn sprinklers) – still use the 60 Hz reference, and we take for granted that these clocks will maintain their time setting, at least to within a few seconds,” the researchers said.
Alex Crees is a writer covering issues related to energy, the environment and politics. Her work has appeared in Fox News and Prevention. Alex earned a bachelor’s degree in journalism from New York University.