Programmable time relays

Programmable time relaysIn practice, the term "relay" (from the French relais, change, replacement) means an electrical or electronic switch designed to close or open certain sections of electrical circuits when the input parameters of the switch are changed.

As a rule, this term is understood precisely traditional electromagnetic relay — an electromechanical device that mechanically closes or opens the output electrical contacts when a small electric current is applied to the coil of the relay coil. The magnetic field arising in the coil causes the movement of the ferromagnetic armature of the relay, to which the contacts that switch the electric circuit are connected.

Thanks to this process, the circuit is switched, closed or opened. Widespread now and solid state relays, in which the switching of the power circuits takes place exclusively thanks to powerful semiconductor switches, which every year become more and more perfect and withstand more and more currents.

modern time relay

There are cases when automatic switching of the circuit is required not at the moment of the control signal, but after a time interval specified by the user. More complex devices are designed for such purposes - time relays... They create a time delay and ensure a certain operational sequence of actions in the circuit elements.

Even before the appearance of microcontrollers, time relays were widely used and their operation was carried out in various alternative ways: due to the properties of RC and RL circuits, thanks to transient processes, using clock mechanisms and even using gear motors.

Modern time relays include a microcontroller, the program in which is quite sufficient to ensure the correct operation of the relay.

programmable relay

Today, programmable time relays are also available on the market, which are able to automate the shutdown and activation of the necessary devices, acting according to a program that is set manually by the user. Now the regulation of the operation of electrical circuits can be carried out in a given mode and in different predetermined time cycles, whether it is switched on for a day, on weekdays, for a week or only on weekends.

Programmable command for time relays to close or open one or more independent electrical circuits, according to time parameters set by the user. The settings are saved in the device's memory and only then the specified program is executed.

programmable time relay

Such devices have found quite wide application in automated equipment control systems and a wide variety of devices, both in production and in the domestic sphere of human life. This includes turning off and on lighting systems, metal cutting machines and other mechanisms in production, ensuring the correct power supply of energy-intensive consumers at increased loads, as well as home automation systems.

The inclusion of users by hours and minutes is carried out at a time specified by the user, and disconnection occurs after a strictly defined time interval. Turn-on conditions can be set, for example turning on the lights for the required number of hours after receiving a signal from light sensor.

Application of programmable time relays

The use of such programmable relays makes it possible to build intuitive systems for automated control of production machines or pumping equipment, as well as intelligent "smart home" systems that increase the comfort of human living conditions.

Programmable relays, like other types of relays, are presented today by many global manufacturers. Traditionally, however, it is an integral design with power connectors, inputs, outputs, a display and a control panel.

For easier setup, the front of the device has a keyboard for navigating through the menus and a display for displaying information. There is also a connector for cable programming. The power supply of the programmable relays is provided by a supply voltage of 12 V, 24 V, 110 V or 220 V.

Read also: Programmable intelligent relays

We advise you to read:

Why is electric current dangerous?