To control various often very powerful circuits and mechanisms using low-current electrical signals or other influence factors (heat, light, mechanics), special devices are used. They are different in power and design, but their meaning is the same - turn on or off the electrical circuit when a control signal is received. The 220V relay also serves to protect the network.
What is an electrical relay
In an electrical relay, one electrical signal controls another electrical signal. In this case, there is no place for changing the parameters of the latter, but only its switching. Signals can be completely different in form, shape and power, but one thing is important - as soon as current begins to flow in the control circuit, the switching circuit is triggered, connecting or disconnecting the load. When the control current disappears, the system returns to its original state.
Electric relay - a kind ofamplifier, if, for example, a weak signal switches a strong one, and at the same time they are similar in shape and type of voltage. You can also consider such a device as a converter if the signals differ from each other in the shape of the voltage.
You can clearly see the action of the relay on the example of an electromagnetic one. Such a mechanism contains a winding with a steel core and a group of contacts that move movably, closing and opening the circuit. A control current is applied to the core coil. This current, according to the law of electromagnetic induction, creates a magnetic field in the core, which attracts the contact group to itself, and it closes or opens the electrical circuit, depending on the type of relay.
Types of relays
The described devices are classified according to several parameters. For example, based on the type of voltage, an AC relay or a DC relay is distinguished. Structurally, such devices differ from each other only in the type of core, or rather, its material. Permanent relays are characterized by an electrical steel core, and they come in two types:
The former differ from the latter in that they can function in any direction of current passing through the relay.
If we consider the type of control signal and the corresponding design of the device, then the latter are divided into:
- Electromagnetic, which contain an electric magnet that switchescontacts.
- Solid State. The switching circuit is assembled on thyristors.
- Thermostat based thermostat.
- Delay relay 220V.
- Optical, where the control signal is the luminous flux.
Voltage control relay
To control electrical networks, or rather, voltage parameters, 220V relays have been developed. They are designed to protect household electrical appliances from sudden power surges. The basis of such devices is a special fast response microcontroller. It monitors the voltage level in the network. If for some reason there are voltage deviations up or down from the permissible limit, then a control signal is sent to the device, which disconnects the network from consumers.
The 220V relay threshold is in the range of 170-250 Volts. This is the generally accepted standard. And when the network is switched off, the control of the voltage level in it continues. When the voltage returns to acceptable limits, the time delay system is activated, after which the devices are powered again.
Such devices are usually installed at the input of the circuit after the electric meter and the circuit breaker. The power of the device must be with a margin to withstand voltage surges when the load circuit breaks.
Time delay relay 220V
The device, the meaning of which is to create conditions where the devices of the electrical circuit operate in a certain sequence, is called a time relay. ToFor example, if you need to create a load switching mode not instantly upon the arrival of a control signal, but after a set period, a certain system is used. There are the following types of named equipment:
- Time relay 220V electronic type. They can provide time exposure within fractions of a second and up to several thousand hours. They can be programmed. The energy consumption of such devices is negligible, and the dimensions are small.
- With solenoid deceleration time for DC supply circuits. The circuit is based on two electromagnetic coils, in which magnetic fluxes simultaneously occur, directed in the opposite direction and thus weaken each other for the response delay time.
- Devices where the response time is slowed down by a pneumatic process. The shutter speed can be within 0.40-180.00 seconds. The delay in the operation of the pneumatic damper is carried out by adjusting the air intake.
- Devices on the anchor mechanism or clockwork.
Intermediate relay 220V
Such a device is considered an auxiliary device and is used in various automatic circuits, as well as in control. The purpose of the intermediate relay is the disconnection function in the contact circuits of individual groups. It can also turn on one circuit and turn off another at the same time.
Schemes for switching on a 220V intermediate relay are of two types:
- According to the shunt principle. In this case, everything that feedsvoltage is applied to the relay coil.
- By serial type. Here, the winding of the mechanism with the switch coil is connected in series.
In the relay circuit, depending on its design, there may be up to three windings on the coils.