The operating time depends on the type of contactor electromagnet and its control mode. C contactor a threephase starter b singlephase starter type 25 nonreversing contactors and starters c306 27 nonreversing starters xtob 30 nonreversing starters c440 eol 65 reversing contactors c 2 5 d n a 2 1 5 a a 1 6 1 8 4 contactor frame size a compact, singlepole b compact, twopole c compact, singlepole w. Motor logictm solid state, tesys t communicating solid state, adapted bimetal, adapted tesystm solid state and melting alloy types. The contactor in a relay is where the highpower signal is switched. Wiring diagram book a1 15 b1 b2 16 18 b3 a2 b1 b3 15 supply voltage 16 18 l m h 2 levels b2 l1 f u 1 460 v f u 2 l2 l3 gnd h1 h3 h2 h4 f u 3 x1a f u 4 f u 5 x2a r. Wago 221412 levernuts 2 conductor compact connectors. Contactor a control device that uses a small control current to energize or deenergize the load connected to it. Under normal power system operation, a protective relay remains idle and serves no active function. Introduction a contactor is an electrical device which is used for switching an electrical circuit on or off. Electrical standards for contactors ac1, ac2, ac3, ac4, dc1, dc2 dc3. Scn1, n2, n2s, n3 long electrical life 2 million operations ac3 duty easytoread front display type, ratings and terminal numbers singlesidemounted coil terminal.
In semiconductor testing, contactor can also refer to the specialized socket that connects the device under test. Relays are important in the control and protection of all types of large electrical gear. Contactor types, structure and working principle xinli. These electrical devices are also used for the purpose of stopping, reversing and protecting electric motors. In process industries, a contactor is a vessel where two streams interact, for example, air and liquid.
Contactor relays eaton wiring manual 0611 53 55 the system and the standard european standard en 50011 terminal markings, distinctive numbers and reference letters for certain contactor relays has a direct bearing on the use and application of the modular system. Note that one one of the contactor acts as a switch for the start button. The duty of electrical contractor is categorized by the types of electrical loads used such as inductive, or resistive or capacitive and duty cycle such as plugging or runtime breaking, short circuit breaking etc. Lever nuts, 75 pcs wire connector assortment pack compact splicing connector lever nut kit for electrical wires solid stranded flexible wires a221412. Contactors are most commonly used for controlling electric motors. However, the basic difference between the relay and contactor is that the contactor is used in.
According to their rating, contactors are classified into the following. Electrical contractors handbook ech subject table of contents effective. The coil of the contactor can be powered indifferently in ac or. Typical electrical drawing symbols and conventions. Working of a contactor different types of contactor devices 1. Twentyfive is the most significant number in the 2018 profile of the electrical contractor research study findings. Knife blade switch the knife blade switch was used earlier in the late 1800s. But when fault or undesirable condition arrives relay must be operated and function correctly. Contactors, overloads and manual motor starters carlo gavazzi. An auxiliary contact on the contactor keeps the contactor coil energised after the start button is released. It means youre wearing many more and different hats than ever before. Relays a relay is defined as an electrically controlled device that opens and closes electrical contacts, or activates and deactivates operation of other devices in the same or another electrical circuit. Types of motor starters 25 standards and ratings 26. In summary, contactors operate electromechanically and use a small control current to open and close the circuit.
The basics of contactors commercial electric products. There are various types of contactors, and each type has its own set of features, capabilities. Best electrical lecture notes pdf download class tutorials. These starters are extremely easy and straightforward to operate and do not require expert intervention. Contactors are used in applications ranging from the light switch to the most complex, automated industrial equipment. A contactor is typically controlled by a circuit which. At the same time observations can be made to judge if the contactor operates well in the application and that no signs of abnormal wear or damages are present on the contacts. Electrical characterization of test sockets with novel contactors article pdf available in ieee transactions on device and materials reliability 141. Selection guide tesys contactors tesys d low consumption contactors. Types of motor starters there are several types of motor starters. A contactor is an electrically controlled switch used for switching a power circuit, similar to a relay except with higher current ratings.
In addition to the simplicity which they offer in project engineering, panel building. Maximum backup fuse for shortcircuit protection gl and gg. The coil energizes the contactor, moving the contacts into position. Manual guidelines for contactor inspection and maintenance. Applications include lighting circuits, heaters, and transformers. Static switching control is a method of switching electrical circuits without the use of contacts. The contactor switch also has a voltage and current rating that tells you how much power you can expect the relay to conduct before the contacts fail. Contactors are used by electrical equipment that is frequently turned off and on opening and closing the circuit, such as lights, heaters, and motors.
Contactors and relays 5 5 contactor relays contactor relays contactor relays are often used in control and regulating functions. Ratings of a contactor are given according to the pole of the contactor. In most cases, the contactor does not simply wear out from normal use. Pdf electrical characterization of test sockets with. Two types of relay technology are available, mechanical and solid state.
As the name suggests, a starter is an electrical device which controls the electrical power for starting a motor. When a relay is used to switch a large amount of electrical power through its contacts, it is designated by a special name. White paper on different types of relays the relay is an automatic protective and switching device which is capable of sensing abnormal conditions in electrical circuits. The more expensive the electrical gear, the greater the number of relays that will generally be used. Electrical contactors, as shown in figure 1, are switches that are turned on and off with electrical power rather than with the direct push of a button or flipping a toggle switch figure 1 electrical contactor figure 2 plugin relay for all intent purposes, a contactor is a relay, as shown in figure 2. In particular, large electrical gear as generators, motors and transformers depend on relays for correct and safe operation. This is to ensure a trouble free operation of the contactor until the next service is required see next section interpreting levels of electrical contact wear. Since a contactor should last for years, dont automatically replace one that fails with an identical unit. Today, after decreasing over the subsequent 14 years, that number is only 25 percent, which indicates. A contactor is an electrically controlled switch used for switching an electrical power circuit, similar to a relay except with higher current ratings. The closing time is measured from the time the coil power supply is.
The contacts are the current carrying part of the contactor. A contactor can stand on its own as a power control device, or as part of a starter. A contactor uses contact blocks of silvercoated copper, which are forced together to make close or are separated to break open a circuit with the help of magnetic coil. Contactors typically have multiple contacts, and those contacts are usually but not always normallyopen, so that power to the load is shut off when the coil is deenergized. There are various types, which the standard differentiates between by means of. Electrical standards for contactors ac1, ac2, ac3, ac4. Whatever the application, the function of the contactor is always the same. A simple circuit diagram either of the two start buttons will close the contactor, either of the stop buttons will open the contactor. A contactor is controlled by a circuit which has a much lower power level than the switched circuit. This video explains the principle of operation of contactors. The basics of contactors contactors are useful in commercial and industrial applications, particularly for controlling large lighting loads and motors. Simple catalog numbering for easy and fast ordering flexible with five overload relays.
It is also defined as the contactor is an electrically operated switch which is used for switching an electrical power circuit. The contacts of the contactors are known for their rapid open and close action. Type s ac magnetic contactors 3640 class 8502 3640 iec contactors 4142 iec contactors and auxiliary contact blocks 41 input modules and reversing contactors 42 type s ac magnetic starters4350 class 8536 4350 8538 and 8539 45,49. An electrical connector is an electromechanical device used to join electrical conductors and create an electrical circuit. It also depends on factors like fault withstand current, coil voltage and so on. Contactors electromechanical relays electronics textbook. These are operated to open or close the load contacts in response to one or more electrical quantities like voltage and current.
The largescale revamp calls for the coordinated skills of all three types of electrical contractors. Type s starters are easy to customize and provide excellent service life. It belongs to a kind of control device, and it is one of the most widely used lowvoltage electrical appliances in electric drive system, machine tool equipment control circuit and automatic control system. In the 2004 study, traditional electrical powerdistribution made up 69 percent of the ecs revenue.
Contactors are electrically controlled switching devices used for switching of electrical circuits. The connection may be removable as for portable equipment, require a tool for assembly and removal, or serve as a permanent electrical joint. Protective relays work in concert with sensing and control devices to accomplish their function. However, the two most basic types of these electrical devices are. The contactor is a voltagecontrolled switching device suitable for systems that frequently turn on and off the acdc circuit. Ip rating for electrical enclosure 11kv415v over head line specification as per rec abstract of nati skip to content engineering interview questions,mcqs,objective questions,class notes,seminor topics,lab viva pdf free download. Reversing contactor type 3pole lc2 d09 lc2 d12 lc2 d18 4pole lc2 dt20 lc2 dt25 lc2 dt32 pages contactors 245012 to 245025 reversing contactors 245032 to 245103 1 with low consumption kit la4 dbl see page 245117. See gasliquid contactor a contactor is an electricallycontrolled switch used for switching an electrical power circuit. Types and revolution of electrical relays introduction.
However, like any other device, they are not infallible. Pressing the stop button breaks the control circuit to. Introduction motor starters are one of the major inventions for motor control applications. Instead, take a few moments to see if there is an obvious problem. They are used in large quantities for the indirect control of motors, valves, clutches and heating equipment. Contactors are used when no overload protection is necessary, and at lower levels of electrical current. When the start button is released its contacts spring open. It was probably the first ever contactor that was used to. Electrical and mechanical interlocks tethered remote control topbottom cable entry seismic certified wallmount and freestanding engine start contacts form c enclosure types service entrance design marked for use at 100% of amperage rating and fully ul 1008 listed integral overcurrent protection with. Selection guide tesys contactors tesys d contactors. Square d type s contactors and starters schneider electric. Manual starters manual starters are devices that are operated manually.