Construction of some relays is done with a kind of shock absorber mechanism that is attached to the armature that results in preventing immediate, full motion when the coil is either energized or de-energized. This addition provides the timer relay the property of time-delay actuation. Time-delay relay contacts need to be specified not only as either normally open or normally closed but even for the fact that the delay operates in the direction of closing or the direction of opening. Use of Time-Delay Relays in Industrial Control Logic Circuits Time-delay relays in industrial control logic circuits are very important. Some examples of their use include: Conveyor belt sequence delay: The conveyor belts need to be started in reverse sequence (the last one first and the first one last), when there is an arrangement of multiple conveyor belts to transport the material so that material doesn’t get piled onto a stopped or slow-moving conveyor. Engine auto start control: To power, emergency generators engines that are needed are often equipped with auto-start controls that if the main electric power fails allow for automatic startup. 5v timer relay help sequence these events for the proper start-up of the engine. Motor soft-start delay control: Reduced voltage can be switched for a softer start and less inrush current instead of starting large electric motors by switching full power from a dead stop condition. Full power is applied after a prescribed time delay (provided by a time-delay relay). Flashing light control (time on, time off):
In conjunction with one another two time-delay relays are used so that for sending intermittent power to a lamp it can provide a constant-frequency on/off pulsing of contacts. Advanced Timer Features To provide shock absorption that is needed to delay the motion of the armature the older mechanical 24v timer relay used pneumatic dashpots or fluid-filled piston/cylinder arrangements. To generate a time delay newer designs of time-delay relays use electronic circuits with resistor-capacitor (RC) networks and then energizes a normal (instantaneous) electromechanical relay coil with the electronic circuit’s output. Compared to the older mechanical models the electronic-timer relays are more versatile and less prone to failure. Follow us on facebook
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Meba Electric Co., Ltd is a professional manufacturer and supplier of highly designed and premium quality electrical appliances. We always focused on developing our capacity and increasing the efficiency to compete in the current market. Archives
April 2024
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