Clocks are an integral part of our society. Clocks measure our waking hours, our working hours, and even our leisure hours. They offer a standardized measurement for time, one of our most valuable commodities. And when clocks don't work, we're late for something. Here's how to keep them running on time.

How Does It Work?

A clock is an instrument for measuring time. Electric clocks rely on the 60-cycle-per-second alternations of household current (AC) to ensure accurate timekeeping.

A synchronous motor inside an analog clock drives a gear train, which in turn moves the clock's hands. Older clocks may have metal gears, but the gears of new clocks are generally made of plastic to reduce operating noise--and manufacturing costs.

When an alarm is set on an analog clock, a cam gear presses against a lever, which in turn holds a vibrator arm above a frame. At the preset time, the cam gear moves outward, allowing the vibrator arm to repeatedly contact, or buzz, the frame.

Digital clocks rely on electronic circuitry instead of gears and levers. If a component fails, however, the clock will probably have to be replaced because most are difficult to repair.

What Can Go Wrong?

So why won't your electric clock work? On analog clocks, hands can work loose, gear teeth can wear down or break, the clock may not run at all or may keep time poorly, or the clock can be noisy. On digital clocks, the cord or battery may not deliver power to the motor.

Fix-It Tip

With an inexpensive clock, it may not be worth your time to attempt repair. But before tossing the entire clock, check a local craft or electronic shop for a replacement digital clock mechanism.