In general contactors are intended to control >contactor has a hold on contact whereas relay has no such provision < Hold on contact is something that can be applied to either component. The contactor is larger and capable of carrying more amperage than a relay. Twitter. The distinction of a relay as switching AC (almost always only single phase) or DC pilot/control signals vs a contactor actually switching the full line voltage and current (often three phase) to lights, motors, etc. Control relays are an extremely important electrical part, and they play a vital role in today's electronic devices. With voltage ratings from 12V DC up to 1200V DC, contactors are a cost-effective, safe, lightweight solution for DC high-voltage power systems. Springer Controls offers a complete line of electrical controls including IEC contactors and starters, 22 mm & 30 mm pilot devices, power switching devices, crane & hoist controls, signaling devices, temperature controllers and terminal blocks. You can use a safety relay of that type in category B, 1 and 2 circuits too. Using the test button, it is possible to test the control wiring. NC contacts should be capable of direct switching of contactor coil. The light sensor is connected to the transistors which open or close, supplying the relay's load with power. This article discusses control relay switch chattering or rapid, repeated clicking noises, their cause, meaning, and repair. What is the difference between a contactor and a relay? January 24, 2019. Protective relays and circuit breakers must work together to isolate a fault. The control inputs are connected internally to an LED, which shines across an air gap to light sensors. Wired to provide a control sequence, relays may also be used for simple control schemes where a PLC would prove uneconomical. Relay vs Contactor-Difference between Relay and Contactor. The relay contacts are operated when the relay coil is energized (24 V DC). The contactor is the relay to use when a circuit must support an even heavier current load (typically 100-600 amps). When a transistor is closed, current can flow freely through the relay, causing the load and power supply to be connected. Contactor relays Contactor relays Contactor relays are often used in control and regulating functions. The use of a contactor is similar to the relay . As known, contactor is used to switch higher capacity than relay. In a relay-based control system, relays are used to interface the input devices with the output devices. A relay is an electrical switch that has a set of control terminal & contact terminals. In low-voltage (below 1,000 volts) industrial electricity, there is some overlap in these categories. 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. If anything, it would more apply to the relay than the contactor because the hold is a smaller voltage to keep the coil engaged than what a contactor … In general, an electro-mechanical contactor is rated for a specific Contact of a relay can be used to connect or disconnect the coils of a contactor. 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. I suspect this is because modern relays are very capable and in the field prove remarkably reliable. A contactor is an electromechanical control device that used to make or break the connection between the load and power supply. But the device used for higher current carrying application is known as a contactor and the device used for lower current applications is known as Relay. Relay is an electro-mechanical switching … It includes a contactor as an essential component, while also providing power-cutoff, under-voltage, and overload protection. Contactors and Relays perform the same task of switching a circuit. In this, we are going to see the 7 difference between relay and contactors. Test button. Orig. This page compares Relay vs Contactor and mentions difference between Relay and Contactor.. What is Relay? The contacts are the current-carrying part of the contactor. It is but one component of a starter and is rated by voltage. Control relay switch chattering noises or chattering at contactor switches in air conditioners, heat pumps, water pumps. The control terminals is operated by a single or multiple control signals to swtich the contact terminals. Contactors and relays perform the same task and operate under very similar principles. Easy to install and mounted in multiple orientations. Examples of Motor Control Summary. A contactor is a special type of relay used for switching an electrical circuit on or off. Installation contactor VSM220 The manual control contactors are designed for auxiliary and power switching, have a front panel switch and have a manual forced boiler operation mode. It is used for switching an electrical circuit on and off. Here are a few of the basic differences that distinguish different types of relay and contactor switches. A relay is used to energize the starter, which, in turn, switches the motor voltage while the PLC controls the relay. A protective relay protects the electrical system by trying to determine what is normal and abnormal and tells the circuit breaker to open when a problem is detected. The electromagnet (or "coil") provides the driving force to close the contacts.The enclosure is a frame housing the contacts and the electromagnet. Linkedin. A contactor is really just an overgrown relay. The contactor is mostly used in applications where higher current carrying capacity is involved, while the relays are used for lower current applications. All magnetic contactors are a type of relay, but relays can be significantly more complicated than contactors. Figure 3: Relay-based control system. This includes power contacts, auxiliary contacts, and contact springs. The same procedures can be used to check both contactors and relays. There are three areas of problems encountered with contactors and relays the contacts, the coil, and the mechanical linkage. • The relay is controlled device which opens and closes contacts in order to effect operation of … not surprisingly, the noise from a contactor is much louder than a small relay. Control Relay also known as a relay, is an electromagnetic switch…. A contactor has three components. The contactor applies voltage to a contactor coil to close the contacts and to supply and interrupt power to the circuit. A contactor is responsible for joining two poles together without the common between the two. The Basics. So, if a relay has a same switching current with a contactor, which one to choose? A control relay is, in essence, a switch that is controlled by electrical current.A control relay is an electrical component that opens or closes a switch in order to allow current to flow through a conducting coil, with the coil not coming into direct contact with the switch. When you look in the data sheet for a safety relay you will find that it can be used up to a certain safety level. Top 7 Difference Between Contactor And Relay: Relay and contactor are functionally doing same duty, but the major difference between relay and contactor is that, contactor can carry huge amount of current but relay can carry only less amount of current from 0.1 A to 20 A. Any one of the the three areas can cause a contactor or relay to malfunction. The contactors is primarily used for switching larger power circuits (such as motors, for example), since the control logic components cannot meet the current & voltage duty of the power circuit. In addition to the simplicity which they offer in project engineering, panel building, commissioning and maintenance, the high Pinterest. seems like a highly useful distinction. A relay consists of a coil and switching contacts. An electro-mechanical contactor is a device that opens or closes a contact, allowing electricity to be switched fully on and fully off. Relay-based Control System . 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. An electrical control signal triggers the opening or closing of the contact or contacts. Comparing PLC vs Relay tablewise! A PLC may be used to control the operation of a medium-voltage motor, perhaps 2,300V or 4,160V. They are used for switching relatively high power circuits using low power signals. Share. Simply Buy Co., Ltd. is a leading new energy controls supplier, we major focus on electrical, pneumatic and automation controls for industrial and commercial. 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. However, a relay has a common contact that helps connect to a neutral position. A motor starter is simply a contactor PLUS an overload relay and is rated by motor HP or amperage. 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. A magnetic starter is a device designed to provide power to electric motors. They are used in large quantities for the indirect control of motors, valves, clutches and heating equipment. By common usage, the term, “contactor” is applied to a special type of device that is functionally similar to the relay. # 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. 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 They are provided with two auxiliary contacts – one NO (97-98) and another NC (95-96). The relay is usually used in the electrical control circuit, it's used to extend the contact capacity of a micro or small relay, so as to drive larger load. Generally, a relay has several opening and closing contacts. Chattering Relay Switch Noise Causes & repairs for clicking chattering relay switches in HVAC, Pump, & other controls. 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