A contactor is really just an overgrown relay. Email. If you see from the application point of view, you would have seen contactors placed in control panels of industrial motors or other heavy loads. Relay-based Control System . # Contents: PLC Relay: 01: Basic: Programmable Logic Control (PLC) is a solid-state computerized industrial controller that performs software logic by using i/o, CPU, memory. I find speaking to many sparks and automation engineers, that the sparks lean towards contactors, yet the automation engineers seem happy for relatively low loads to use relays. NO contact is for trip signaling and NC contact is for disconnecting the contactor. What is the difference between a contactor and a relay? Motion Control; Motor Control; Contactor vs. Relay. A relay is an electrical switch that has a set of control terminal & contact terminals. The system controls the contactor on/off with temperature controller (PID regulator with relay control output) and intermediate relay and then controls the electric heater. There are three areas of problems encountered with contactors and relays the contacts, the coil, and the mechanical linkage. Yet, a contactor is not normally called a “relay.” Rather, the term, “contactor” is used to describe a type of device that is used very much in the same manner as a relay. An electrical control signal triggers the opening or closing of the contact or contacts. Twitter. In addition to the simplicity which they offer in project engineering, panel building, commissioning and maintenance, the high Chattering Relay Switch Noise Causes & repairs for clicking chattering relay switches in HVAC, Pump, & other controls. As known, contactor is used to switch higher capacity than relay. Types of relay… There are different types of Control Relays depending on the operating principle and structural features…Circuit Diagram…Contact Types…Differences between conductors Share. Facebook. Wired to provide a control sequence, relays may also be used for simple control schemes where a PLC would prove uneconomical. An electro-mechanical contactor is a device that opens or closes a contact, allowing electricity to be switched fully on and fully off. • The relay is controlled device which opens and closes contacts in order to effect operation of … seems like a highly useful distinction. When a transistor is closed, current can flow freely through the relay, causing the load and power supply to be connected. They are used in large quantities for the indirect control of motors, valves, clutches and heating equipment. Control relay switch chattering noises or chattering at contactor switches in air conditioners, heat pumps, water pumps. Contactor relays Contactor relays Contactor relays are often used in control and regulating functions. The relay contacts are operated when the relay coil is energized (24 V DC). Pinterest. The contactor is the relay to use when a circuit must support an even heavier current load (typically 100-600 amps). A PLC may be used to control the operation of a medium-voltage motor, perhaps 2,300V or 4,160V. In this, we are going to see the 7 difference between relay and contactors. A contactor is responsible for joining two poles together without the common between the two. But there some relays can switch high current too, such as, some power relays can switch current beyond 100A, and there are contactors to switch only 160A. Simply Buy Co., Ltd. is a leading new energy controls supplier, we major focus on electrical, pneumatic and automation controls for industrial and commercial. 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