Ndifference between relays and contactors pdf free download

Relays, contactors, solenoids and for more information pdus. The main difference between contactors and relays is the loads that they are meant to handle. They both are commonly used in industrial and commercial applications, and function in almost the exact same way. Pdf magnetic contactor 1 pole relay wiring free files. Ssrs are not very different in operation from contact relays electromagnetic relays. Dual iec and nema terminal markings for ease of wiring anywhere in the world.

Our motorrated contactors are available from nema size 009, in open and enclosed design for fullvoltage starting of ac motors. Push the exposed end into the contactor slot, then tighten the screw to hold it in place. This includes power contacts, auxiliary contacts, and contact springs. Large electric motors can be protected from overcurrent damage through the use of overload heaters and overload contacts. The contacts are the currentcarrying part of the contactor. Auxilary and power contactor,it can make,break and carry only in overload and normal condition. Contactors for safety applications motor protection and. Devices switching more than 15 amperes or in circuits rated more than a few kilowatts are usually called contactors. While contactors can handle enough current to help power heavy equipment, they also come with the highest price tag and require the most space, whereas relays require little space and can be purchased very inexpensively.

A relay is normally used in appliances below 5kw, while a contactor is preferred when the appliance is heavier. Ssrs solid state relays use semiconductors for nocontact operation. Contactors are used for devices that pass more than 15 amps or loads of more than 3kw. Episode 28 the difference between contactors and relays. If the seriesconnected heaters get too hot from excessive current, the normallyclosed overload contact will open. E3 and e3 plus electronic overload relays allenbradley. The sc series is a range of long servicelife and highperformance contactors. The more expensive the electrical gear, the greater the number of relays that will generally be used.

These contactors are very commonly used in industries for control of electric motors. The coil of the contactor can be powered indifferently in ac or. Contactors and overload relays 4 allied electronics. Abbs complete range of thermal overload relays provides.

Customers are encouraged to migrate to the e300 electronic overload relays coupled with the new devicenet or ethernetip communication module. Two typical manual contactors still in use today engineers eventually made a breakthrough with the magnetic contactor. Study 29 terms unit 19 motor controls flashcards quizlet. How to wire a contactor steps with pictures wikihow pdf. Describe the difference between inherent and external motor protection. What is the main difference between a contactor and a magnetc motor started. Standard type magnetic contactor, magnetic starter. Features of new electromagnetic contactors and switches hs series. Difference between contactor and relay compare the. Relay design id relays are either normally open or normally closed. The msn series contactors, starters and relays can be installed on a mounting rail 35mm width. Understanding relays page 4 autoshop, all rights reserved.

Shop our parts hvac online store for transformers, contactors, and relays hvac supplies and accessories. Iec contactors relays springer controls company 96074 chester road, yulee, fl 32097 904 2250575 fax. Unit 11 contactors, relays, and overloads flashcards quizlet. Breakdown voltages volt amperes coil voltage rating all terminals 60 hz rms contact material electrical life mechanical life open max. Rather, the term, contactor is used to describe a type of device that is used very much in the same manner as a relay.

Inherent motor overload protection is provided by sensing devices within the motor and external overload protection is applied to the current passing device, the relay, the contactor, or the starter. Controls contactors and contactor assemblies contactor. Ssrs, however, consist of electronic parts with no mechanical contacts. The main difference between contactors and starters is the use of overload heater element a sensitive coil which monitors the generated heat by excessive current and changes in ambient. The contactor relay contacts themselves constitute a considerable safety feature. A contactor joins 2 poles together, without a common circuit between them, while a relay has a common contact that connects to a neutral position. The terminals of these coils are arranged on the contactor with simple wiring. Definite purpose motor control contactors and starters. Suitable for low dutycycle applications requiring low cost switching of single and threephase. Contactors are used for loads that have high voltages, high currents, or both.

However, the basic difference between the relay and contactor is that the contactor is used in applications with. Adaptability made easy definite purpose contactors and starters are electrically operated switching devices specifically designed for the heating, ventilation, air conditioning and refrigeration hvac industry. They both are commonly used in industrial and commercial applications, and function in almost the. Magnetic suppression and arc dividers are typically utilized when switching multihorsepower motors. This article clarifies the differences between the two devices to remove any confusion once and for all. Our contactors can also be used for nonmotor and lighting loads. Depending on the operating principle and structural features, relays are of different types. The ax contactor range offers exceptional reliability and performance in a brilliant. Devices of the 3th2 series are also available for connection with flat connectors and solder pin connectors. Heating and cooling equipment require switching devices that are heavy duty and can operate for thousands of cycles. Relays and contactors type 91 general purpose relays type engineering design data magnet coil rating operation in % nom.

Furthermore, the distance between the center of the rail and the coil terminals is unified at. These classifications include electromagnetic, solid state, high voltage, thermal relays, and so on. Nema contactor and starter specifications technical data. Also find hard to find transformers, contactors, and relay replacement parts. Contactors are typically built for and used in 3phase applications where a relay is more commonly used in single phase applications. Contactors and motor starters that in turn will switch the motor on or off. The motor statrter is made up of a contactor with an overload relay attached physically and electrically to it. Switches, circuit breakers, and contactors are used to control what parts of an electrical system are energized or deenergized. Contactors a contactor is a control device that uses a small control current to energize or deenergize the load connected to it.

No part of this wiring manual may be reproduced in any form. Both these devices are used for similar purposes and hence people are often confused about the difference between a contactor and a relay. Variations of manual contactors are still in use today. Contactors, and relays for hvac are available at wholesale and quantity pricing. The rsc series is designed for din or panel mounting and features zero switching voltage, builtin transient protection, and led indication. Contactors and relays perform the same task of switching a circuit. Difference between contactor and relay difference between. A summary of the difference between contactors, motor starters, relays and circuit breakers. What is the difference between solidstate relays ssrs and contact relays. Contactors and reversing contactors schneider electric. Plug the power wire into the first auxiliary port if you are using one. Download magnetic contactor 1 pole relay wiring free files.

The magnetic starter is very similar to the magnetic contactor in design and operation. Jun 10, 2014 contactors and relays perform the same task of switching a circuit. 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. All dil contactor relays have doublebreak contacts.

Unit 19 motor controls big book flashcards quizlet. Relays and contactors terminal type coil grounded to case spno terminal type isolated coil spno terminal type isolated coil spdt 1. Contactors and relays contactor relays moeller wiring manual 0205 53 5 the system and the standard european standard en 50011 terminal markings, reference numbers and reference letters for certain contactor relays has a direct bearing on the use and application of the modular system. A general purpose motor control contactor may be suitable for heavy starting duty on large motors. Difference between contactors and relays electrical classroom. Sc03 to scn3 smallframe contactors provide snapon fitting of numerous optional units, such as auxiliary contact blocks, coil surge suppressors, and operation counters. Contactors and starters with a broad portfolio that includes everything from phase, voltage and current monitoring relays to motor protection breakers, eaton offers the protection your system needs against equipment failure and danger caused by voltage faults, current. Difference between ssr and contact relay faq india. Choosing between contactors and relays for your application. Unlike relays, contactors are designed to make and break higher powered circuits without being damaged. Power contactors type engineering design data operation in % of nom.

Therefore, this document is intended to describe about a few basic types of relays that are popularly used in typical loadcontrol. Make sure you dont see any stray wire strands hanging out from. The plugin bases for lzslzx coupling relays are also available with plugin terminals. Relays are classified into several types based on their functionality and application they are implemented for. By design and construction they ensure potential isolation between the actuating circuit and the operating circuit, in the deenergized state, between the contact input and output. Both of them are electrically operated switches used for control and switching of loads.

Both have the feature of operating contacts when the coil is energized. Overcurrent protection is protection against excessive currents or current beyond the acceptable current rating of equipment. However, the basic difference between the relay and contactor is that the contactor is used in applications with higher current carrying capacity, whereas the relay is used for lower current applications. Breakdown voltages coil rating coil voltage rating all terminals 60 hz rms contact material electrical life mechanical life nominal open max. These relays are also called as directional relays. Hence contactors are used in the switching of heavy loads and power circuits whereas relays are used in the switching of. A circuit breaker is a simple switch,it can make,break and carry current in normal,overload and short circuit condition. Dec 11, 2017 much like a relay, a contactor is an electrically controlled switch.

Identify all main components of a diesel engine starting system 2. Difference between overcurrent protection and overload. Download 2d or 3d files according to your needs step. We offer the best quality hvac contactors and relays you can find. The action of the plunger is used to close or open sets of contacts. In addition, these starters are available with contactors up to. Relays tend to be of lower capacity and are usually designed for both normally closed and normally open applications. Ofun forklift waterproof single pole dc magnetic main. Environmentally friendly contacts are cadmium free and nonmetallic materials are asbestos, halogen and cadmium free. Long life the jm family of contactors and relays offers superior performance.

Contactor and relay are two terms often encountered when dealing with electric circuits. The only difference between them is their power rating. Crane control contactors and relays 67 october 2008 low voltage monitoring relays technical data and specifications frame relay download frame relay pdf ebook frame relay frame relay ebook author by paul glennon frame relay ebook free of registr. Bulletin 193 iec and 592 nema e3 and e3 plus electronic overload relays are discontinued and no longer available for sale. Understanding relays page 6 autoshop, all rights reserved. Tesys d class 10 and 20 overload relays standard tripping time. Thanks to the wide operating range of the af contactor it can operate just as well in europe as in asia or north america. Switches, circuit breakers, and contactors are used to control what parts. Difference between contactor and relay since a contactor is required for a higher load, a relay is always cheaper than a contactor. When a relay is used to switch a large amount of electrical power through its circuits, it is given a new name, a contactor. Contactors are rated by designed load current per contact pole, maximum fault withstand current, duty cycle, design life expectancy, voltage, and coil voltage.

Electrical controls for heating and air conditioning, contactors, relays, transformers, sequencers, time delays. Possible to print the page to a pdf file or from your printer. The main difference between contactors and relays are the loads that they. The contactor is the relay to use when a circuit must support a heavy current load. Including nonreversing and reversing contactors and starters as well as overload relays and accessories, contactoroverload relay brings lsis to a. What is the difference between overcurrent protection and overload protection. Contactors generally are spring loaded to prevent contact welding. In general contactors are intended to control higher levels of current. 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. The enclosure is a frame housing the contacts and the electromagnet. A contactor is an electrical device which is used for switching an electrical circuit on or off. Contactors up to 96 a offer free choice of coil terminal access and can take side and.

A contactor is a large relay, usually used to switch current to an electric motor or another highpower load. Download fulltext pdf comparision of selected contact materials used in lowvoltage relays article pdf available january 2015 with 3,736 reads. Pdf comparision of selected contact materials used in. Spacequalified relays and contactors 28 vdc contactors 270 vdc contactors ac contactors kilovac high voltage relays n voltage isolation to 70 kv n current carrying capability to 110 a n service life to 10 million cycles n various contact forms available n flange, panel and pc board mounting styles n optional coils, mountings and terminals. Contactors electromechanical relays electronics textbook. A3 nonreversing minicontactors nonreversing ac, dc, 3 pole. Relay operation all relays operate using the same basic principle. Cb certificate afs80, afs96 3pole contactors english pdf certificate 1sbc100214c0201 main catalog motor protection and control manual motor starters, contactors and overload relays pdf edition march 2019 english pdf catalogue 1sbc100208c0203 af contactors for safety applications english pdf catalogue. While power relays are called contactors, control relays are simply called relays.

Compact size the contactor relay mounting profile is approximately 1 34. 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. Additionally, contactors are commonly rated for up to v, while relays are usually rated to only 250v. They are subjected to stringent quality assurance inspections and testing procedures. Much like a relay, a contactor is an electrically controlled switch. These are operated to open or close the load contacts in response to one or more electrical quantities like voltage and current. With conventional contactor technology, different contactors were needed for different network voltages. We also offer a variety of nema contactors with marine certification for many marine and offshore applications. The basic principle of operation of the contactor and the relay are the same. The manual contactor was a big improvement over the knife blade switch. Find the a1 port, then get the 120volt wire on the accessory you wish to connect. Download magnetic contactor 1 pole relay wiring pdf.

Unlike generalpurpose relays, contactors are designed to be directly connected to highcurrent load devices. Enclosures are made of insulating materials such as bakelite, nylon 6, and. Contactors and relays contactors dil, overload relays z eaton wiring manual 0611 510 5 5 rated operating current ie a ac3 at 400 v max. Here you will find our selection of top quality contactors and relays. The bending difference between onphase and offphase bimetals. Af contactors 3pole contactors and overload relays for. Bar mounted contactors up to 2750 a 900 kw 400 v tesys sk and sk gc minicontactors.

The terms solenoid and relay can often be used interchangeably. Main difference between contactor and starter electrical. Describe the similarities and differences between air, hydraulic, and electric starting systems 3. Contactors up to 150 a for ac3 75 kw 400 v and 200 a for ac1 applications. Compensated relays with manual or automatic reset, with relay trip indicator for ac or dc. Identify all main components of an electric starter motor assembly 4. One or more overload protectors, magnetic coil, and. The electromagnet or coil provides the driving force to close the contacts. The contactor relays and the relays are available with screw terminals box terminals or with springtype terminals. A contactor has a frame, plunger, and a solenoid coil. Class 14 esp100 starters use the same contactors as class 14 nema starters equipped with bimetal overload relays for nema sizes 00 through 4, but are supplied with a class 10, 20, or 30 esp100 solidstate overload relay. Dec 04, 2018 relays and contactors are electrically controlled switching devices.

J motor protection and selection of thermal overload relay. Relays and contactors from general purpose to board. What is the difference between a contactor and a relay. In particular, large electrical gear as generators, motors and. Ce marking is part of an administrative procedure designed to guarantee the free movement of the. Contactor vs relay electrical engineering stack exchange. Each model is identical in electrical characteristics, mounting plate sizes representing the only difference. Magnetic circuit breakers, fuses and overcurrent relays are commonly. The rsc series solidstate relays accept a 432 vdc control input and offer optical isolation between the input and output. Relays are typically integrated into a logic circuit together with other relays. All contactors, thermal overload relays, and auxiliary contact blocks bear the. Main difference between contactor and starter electrical pdf. Power rating of contactors are more than the relays. Monitoring relays monitor a system conditions such as direction of power and accordingly generates an alarm.