Relays and contactors are similar in structure and function, differing mainly in the power range, which significantly determines the applications. Relays are low-cost electromagnetic switches with two switching positions, which are established in a variety of designs. Typical are miniature relays, semiconductor relays and heavy current relays. One important area of application is passenger cars, which are equipped, for example, with fuel pump, flashing and annealing time relays. In addition, rel...
Relays and contactors are similar in structure and function, differing mainly in the power range, which significantly determines the applications. Relays are low-cost electromagnetic switches with two switching positions, which are established in a variety of designs. Typical are miniature relays, semiconductor relays and heavy current relays. One important area of application is passenger cars, which are equipped, for example, with fuel pump, flashing and annealing time relays. In addition, relays are used in a variety of industries. Electromagnetic switches consist of a coil, the armature and working contacts. Functionally, the control circuit generates a ferromagnetic coil field and pulls the armature. As a result of the inclination change of the armature, the working contacts and current in the working circuit flow to the connected consumers. Due to the amplifier function, a small current is sufficient for controlling the working circuit with large current. Voltage and current spikes are uncritical for relays. Relay alternatives are semiconductors and semiconductor circuits. Contactors, also called contactors, are electrically actuated switches, which can be divided into power and auxiliary contactors. For example, auxiliary contactors are used in a self-holding circuit for switching the power contactor on and off. Monitoring tasks can also be carried out by means of auxiliary contactors. An important difference between circuit breaker and relay are the higher loads, Which start at 500 watts and rise to a few hundred kW depending on the model. Contactors have two switching positions (open, closed) and are used for switching circuits. Correspondingly, control applications, for example three-phase motors, pumps, heating and air conditioning systems and building automation, are typical.