Electronic Timers
Electronic timers are essentially quartz clocks with special electronics, and can achieve higher precision than mechanical timers. Electronic timers have digital electronics, but may have an analog or digital display. Integrated circuits have made digital logic so inexpensive that an electronic timer is now less expensive than many mechanical and electromechanical timers. Individual timers are implemented as a simple single-chip computer system, similar to a watch and usually using the same, mass-produced, technology.
Many timers are now implemented in software. Modern controllers use a programmable logic controller rather than a box full of electromechanical parts. The logic is usually designed as if it were relays, using a special computer language called ladder logic. In PLCs, timers are usually simulated by the software built into the controller. Each timer is just an entry in a table maintained by the software.
Digital timers are used in safety devices such as a gas timer.
Read more about this topic: Timer
Famous quotes containing the word electronic:
“Sometimes, because of its immediacy, television produces a kind of electronic parable. Berlin, for instance, on the day the Wall was opened. Rostropovich was playing his cello by the Wall that no longer cast a shadow, and a million East Berliners were thronging to the West to shop with an allowance given them by West German banks! At that moment the whole world saw how materialism had lost its awesome historic power and become a shopping list.”
—John Berger (b. 1926)