The relay is a well known and widely used component. The set of contacts that are open when the relay is not energized are called normally open no contacts and the set of contacts that are closed when the relay is not energized are called normally closed nc contacts. Easy step by step procedure to test an automotive relay, this information pertains to all relay controlled circuits. For this reason it is very helpful to have a versatile test set, which also has the ability to record and analyze transient signals. In this article, we will show what resistance readings you should get when you measure various points of a relay.
Use the sel311l line current differential relay with integral fourzone distance backup for easytoapply, highspeed line protection. Testing the relay out of the case will also produce results that would not check previous tests or future tests since changes in test conditions, such as being near a. Working of relayshow relay works,basics,design,construction. Relays are discrete devices as opposed to integrated circuits that are used to allow a low power logic signal to control a much higher power circuit. How to test a relay the correct way ratchets and wrenches. These relays like the one in the photo in the image viewer are used in the majority of ford vehicles. This is the most comprehensive guide about motor relay testing and dynamic relay testing. But relays use flexible mechanical contacts that wear or burn, effectively.
Properly working protection devices help to maintain the safety of the system and to safeguard assets from damage. Iso relays were designed to try and standardize relay connections, making it easier to test and design systems. Simplified motor relay testing can be ordered as an adobe acrobat pdf digital download, or as a hardcover book that also includes the adobe acrobat pdf digital download for free. The set of contacts that are open when the relay is not energized are called normally open no contacts and the set of contacts that are closed when the relay is not. Acceptance testing, commissioning, and startup will include control power tests, current transformer and potential transformer tests, and any other device testing associated with the protective relay. Understanding and testing the abb red670 distanceline differential relay 10 introduction before starting the relay distance relays 87l2167n are used in line protection and cable protection schemes.
In this video we use a ford relay and an audi for examples. This seminar will introduce the theory and practice of endtoend relay testing. The following figure shows a typical test setup for testing these relays. Understanding and testing the abb red670 distanceline. Thus, the true purpose of preventative maintenance may be lost. How to test a relay with a multimeter step by step guide. The following are amongst the rating type tests conducted on protection relays, the specified parameters are normally to iec 602556. Pdf download links will be sent via email after the order has been processed, usually the same day. Since type testing of a digital or numerical relay involves testing of software as well as hardware, the type testing process is very complicated and more involved than a static or electromechanical relay.
An electrical substation is a subsidiary station of an electricity generation, transmission and distribution system where voltage is transformed from high to low or the reverse using transformers. If a protection system is displaying unexpected behavior, you need to find its cause quickly. 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. This section details the tests required to cover items. A comprehensive overview of inspection and test procedures for protective relays in electrical power systems. The tests themselves will reveal catastrophic failures.
This offer cannot be used towards courses already purchased or added to any other. Typically, a protection system must be visited at its substation installation site and removed from service for this testing. Thus, procedures and records should be designed with preventive maintenance as the guide. How to test a refrigerator relay switch home guides sf. Bench testing the ford 4 or 5 pin relay is not hard to do at all, and in this article ill show you how to do it there are two articles in site about bench testing a ford relay, you can find the other here.
Inspection, testing and commissioning of electrical. It is magnetically operated and is used to control electrical circuits from a distant point. Testing has included system functionality, calibration of measuring relays, and correctness of settings. Protection systems play a key role for the safe and reliable operation of todays electricity power systems. The relay isolates the high power circuit, helping to protect the. Feb 10, 20 here is how you test a car relay the correct way. All you really need to do this is a multimeter set on resistance, however, a 12 volt. Set the relay and calculate the test current as follows.
These two components work together to ensure that the starter operates safely and does not turn the engine over in an unsafe condition. It includes everything ive learned about relay testing since the relay testing handbook. Also mentioned are some preventive measures which may be indicated by the. Step 2 next, reinstall the relay while keeping the wire strand inserted and clear of. The relay testing handbook 8d download ebook pdf, epub. The relay testing handbook valence electrical training services. Page 3 of 15 standard work practice sp0518 ver 2 ergon energy corporation limited abn 50 087 646 062 ergon energy queensland pty ltd abn 11 121 177 802 return the relay scheme to service in an acceptable standard. Automated testing programs are not suited for commission function testing inject current and voltage based on relay s settings not be able to detect setting errors typos bad system data do not test programmed logic or specific io functions. A relay will usually have a coil, pole terminal and a set of contacts. Nov 22, 2018 testing and maintenance of protective relays always begins with a thorough visual and mechanical inspection. In this article, we will show you how to test a relay.
The starter relay and the neutral lockout switch control the starting solenoid. A relay usually gets damaged due to a number of reasons. Must also perform energizing procedures and in service load checks. Caution after each test, cool the relay for minimum 10 minutes. Communication systems required for protection system operation. Relays respond to one or more electrical quantities like voltage or current such that they open or close the contacts or circuits. Facilities instructions, standards, and techniques volume 38 field test procedure for protective relays internet version of this manual created july 2000 facilities engineering branch denver office denver, colorado the appearance of the internet version of this manual may differ from the original, but the contents do not.
Ge power management periodic relay testing 11 get3473b 1 periodic relay testing 1 get3473b 1 periodic relay testing 1. Installation of protection relays at site creates a number of possibilities for errors in the implementation of the scheme to occur. The life test can be suspended after a certain proportion of relays have failed generally the test should be run until at least 50% have failed. On these type of relays, your meter should read zero ohms or produce a beeping sound. How to test a fuel pump relay and other automotive relays. Protection relay guides electrical engineering portal. Each relay needs to be tested to verify it is changing states and each set of contacts needs to be. So it is crucial to test a relay if it stopped working before you replace it or throw it away. Before replacing it by a new start relay, do the test to discover if it really is the part which has a problem. Into this category fall such relays as hfa, hga, hma and perhaps pjv, pjc, and hnc relays.
Principles and practice, including stepbystep dynamic testing procedures that can be applied to any relay element with fixedtime delays. Two types of relay technology are available, mechanical and solid state. When testing another automotive relay, check the diagram on the relay, or the wiring diagram in your car repair manual, because some relay power switches come normally closed and should open when energized usually, these terminals are marked 30 and 87a. The paper first analyzes the functionality of modern state of theart distance protection relays. Apr 01, 20 how to test a car relay and how a car relay works. It controls electrical components like fuel pumps, air conditioner motors and radiator fans. Relay setting x multiples of set current test current. Switch on the test current and check trip time of the relay. A relay is a switching device as it works to isolate or change the state of an electric circuit from one state to another. As the name suggests, one of the main functions provided by the relay is zdistance protection 21 or impedance protection. Testing and maintenance of protective relays always begins with a thorough visual and mechanical inspection. In addition to tests recommended for the overcurrent relay, the directional unit of the di rectional overcurrent relay should be tested for minimum pickup, angle of maximum torque, contact gap, and clutch pressure. Testing procedure it is recommended that only one relay be removed from a circuit at a time if the circuit is still energized.
A mho relay is used for distance protection on a line, a translay relay is used for line differential protection via a pilot scheme, a merz price relay is used for generator. Step 1 to test for intermitted relay failures which are common, remove the relay in question, take a small wire strand, about two inches long and insert it into the relay connector terminal 87 or 30. This site is like a library, use search box in the widget to get ebook that you want. Operation, maintenance, and field test procedures for protective relays and associated circuits iii acronyms and abbreviations a ampere ac alternating current amp ampere ansi american national standards institute bes bulk electric system carma capital asset and resource management application ccvt coupling capacitor voltage transformers co 2. Modern relays have very different characteristics that require a different testing philosophy to ensure that they will operate when required. Testing automotive relays explained defective relay. Testing and cleaning of relays are covered in each of the manufacturers instruction manuals. The starter relay provides power to the starter when the key switch is turned to start.
This hardback book includes most of the volumes in the the relay testing handbook series and includes. Circuit breaker testing is used to test both the performance of individual switching mechanisms and the timing of the overall tripping system. Relay testing and maintenance ge grid solutions online store. Step 1 a relay is used to control switch a high amperage electrical circuit with a low amperage one, for example a radiator fan can pull up to 25 amps when in use, which would burn the computer circuit that controls it, a. Pdf modern integrated protection and automation system have large number of integrated functions which impose additional test. Circuit breaker testing what is circuit breaker testing used for. Protective relay testing and maintenance guide testguy. Iaictliac 60 field relay power system device function. Every once in a while you need to test a relay and when you do its important to check it thoroughly, if.
A technicians approach to cable testing directional. Even if the scheme has been thoroughly tested in the factory, wiring to the cts and vts on site may be incorrectly carried out, or the ctsvts may have been incorrectly installed. Commission testing methods for protection systems mipsycon. Electric power may flow through several substations between generating plant and consumer, and may be changed i. How to test relays ericthecarguy how to test relays is a video about just what it says. With microprocessor relays, the builtin, self testing features can. Elearning tutorials will be a good guide for using different types of relays. Operation, maintenance, and field test procedures for.
If it sounds like something rattles inside, the relay is damaged and needs replacing. However, the following tests should be included for all electromechanical relays. The reason for the discrepancy will not be a change in the relay characteristic but a change in the test conditions, for example, the relays proximity to a steel cabinet. Applications range from classic panel built control systems to modern interfaces between control microprocessors and their power circuits or any application where reliable galvanic separation is required between different circuits. A car relay is a particular kind of remotecontrol switch. Commissioningperiodic maintenancetransfer to test circuittoolssafety measuresmechanical testselectrical. The simplest way of finding this is to use a multimeter with an ohmmeter setting and then measuring the resistance values by checking its terminals. In most cases if you miss diagnose the electrical problem and buy a new relay and it doesnt fix the car, youre stuck with the part you didnt need. Testing automotive relays before replacing them is a good idea and its not to difficult. In addition to the tests previously described, those relays employing devices for time delay for example, capacitors should have an operating time test performed either pickup or dropout, whichever is applicable.
This relay testing book is our core handbook and is used by large organizations across north america in their training programs. The modern relay tester needs to adapt to new technologies to find the most effective test plan possible to make sure the relay has been installed correctly, and will. Circuit breaker testing is essential to ensure the safe and reliable performance of this key link in the power asset chain. Most utilities have a wide variety of test plans and practices. How to test the start relay of the refrigerator compressor. Apply subcycle current differential protection with included fourzone distance and directional overcurrent backup. If the circuit to be tested is in service, one relay at a time should be removed if applicable so as not to totally disable the protection. The most effective way to bench test a solid state relay is to construct a simple test circuit consisting of a dc power supply or battery a 9vdc battery will work fine in most cases and a 60w or 100w light bulb. Otherwise, relay will trip early and you will not get correct results. Operation, maintenance, and field test procedures for protective relays and associated circuits iii acronyms and abbreviations a ampere ac alternating current amp ampere ansi american national standards institute bes bulk electric system carma capital asset and resource management application ccvt coupling capacitor voltage transformers co.
There is a european standard for buchholz relays en502162 2002. The ch2 with the optional energization module is the only tester cirris recommends for testing assemblies with relays. To do this there are only two easy steps to follow. Getting started digital energy multilin getting started 1. Mho relay translay relay merz price relay buchholz relay quite honestly, none of these answers seem 100% right. To test a relay to see whether it is good or defective, the simplest way to do would be to use a multimeter set to the ohmmeter setting and measure various resistance values of the relay. Click download or read online button to get the relay testing handbook 8d book now. Abstractperforming tests on individual relays is a common practice for relay engineers and technicians. Pdf the paper presents a new approach to application testing of protective relays.
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