OS X MAIL RELAYER FREE

Now let's understand how a relay works in a normally closed condition and normally open condition. Instead of a spring, a metal stand like structure can be used.

OS X MAIL RELAYER FREE

Spring (optional):Few relays don’t need any spring but if it is used, it is connected to one end of the armature to ensure its easy and free movement. Yoke:It is a small metal piece fixed on a core in order to attract and hold the armature when the coil is energized. It helps in making or breaking the connection with the contacts connected to it.Ĭontacts: These are the conductors that exist within the device and are connected to the terminals. Movable Armature: A movable armature is a simple metal piece which is balanced on a pivot or a stand. So, when a metal winded with a copper wire and driven by the sufficient power supply, that metal can act as a magnet and can attract the metals within its range. We know that when current passes through the conductor it acquires the properties of a magnet. It is a metal which doesn’t have magnetic property but it can be converted into a magnet with the help of an electrical signal. Here we have explained the internal mechanical parts of a Relay:Įlectromagnet: An Electromagnet plays a major role in the working of a relay. All these are arranged logically to form into a relay. The general circuit representation of the relay is as shown in the figure belowĪn electromechanical relay is basically designed using few mechanical parts like Electromagnet, a movable armature, contacts, yoke, and a spring/frame/stand, these parts are showing in the internal pictures of Relay below. When it is de-energized it goes to its initial position. When the coil is energized the armature moves and is get connected to the normally opened contact till there exists flow of current through the coil. The relay also has two pins namely normally closed and normally opened (NC and NO), the normally closed pin is connected to the armature or the common terminal whereas the normally opened pin is left free (when the coil is not energized). The movable armature is generally considered as a common terminal which is to be connected to the external circuitry. A movable armature consists of a spring support or stand like structure connected to one end, and a metal contact connected to another side, all these arrangements are placed over the core such that, when the coil is energized, it attracts the armature. On a casing, a core with copper windings (forms a coil) winded on it is placed. The following figure shows how a Relay looks internally and how it can be constructed, Generally, a DC signal is used to control the circuit which is driven by high voltage like controlling AC home appliances with DC signals from microcontrollers. It is mainly used to control a high powered circuit using a low power signal. The main operation of this device is to make or break contact with the help of a signal without any human involvement in order to switch it ON or OFF. So relay is a switch which controls (open and close) circuits electromechanically. Dictionary says that relay means the act of passing something from one thing to another, the same meaning can be applied to this device because the signal received from one side of the device controls the switching operation on the other side. There are many types of relay and each relay has its own application, a standard, and generally used relay is made up of electromagnets which in general used as a switch. Again this working principle of relay fits only for the electromechanical relay. It consists of a flexible moving mechanical part which can be controlled electronically through an electromagnet, basically, a relay is just like a mechanical switch but you can control it with an electronic signal instead of manually turning it on or off. Despite the differences in construction, the basic working principle of a relay is the same, so lets discuss more on basic relay operation and take a deeper look into its constructionĪ Relay is an electromechanical device that can be used to make or break an electrical connection.

But, this is a very generalized statement, there are many types of relays and each relay behaves differently as required for its application, one of the most popularly used relays is the electromechanical relay and hence we will focus more on that for this article. To put it in general, relays are just like any other switch which can either make or break a connection, that is it can either connect two points or disconnect it, therefore relays are commonly used to turn on or off an electronic load. From a small traffic signal controller to a complex high voltage switchyard, relays can be found everywhere.

Os x mail relayer