Bite 2, ebite and mbite battery impedance testers threephase ttr transformer turn ratio test set dart cable fault analysis system note. This document will focus only on the tests that are of importance for field installers which are described as installation and maintenance tests. Figure 2typical megger test instrument hookup to measure insulation resistance. This test is often performed by applying an ac voltage but can also be done with a dc voltage. Make sure that all protective fuses, breakers, switches, etc.
This manual refers to any one of the above as a remote device and refers to the three battery impedance testers as the bite. If the installation fails the megger test and physical damage cannot be found, then the complete circuit should be removed and replaced with new roof and gutter heating cable. Megger insulation tester calibration procedure calibration. Record the measurements in the prescribed format proforma for cable. The manual test mode allows the user to initiate the test procedure once the probes are in contact with the object under test. Consult the insulation resistance test equipment manual or manufacturer for insulation resistance testing procedures and recommended safety. The values associated with the testing methods shall be in accordance with. Insulation resistance testing megger testing pat testing pt 2.
Completing turns ratio tests on all transformer taps can be a cumbersome process. Meggar value for 4160 volt cable meggar value for 4160 volt cable gsjhand electrical op 3 aug 08 07. Circuit connections must not be touched during an insulation test. A passion for the business of test and measurement over 100 years ago in 1885 to be precise sydney evershed. Enclosed in a tough case it is both smaller and lighter than its predecessor making it even easier to carry and store. Connect the meggers negative lead to the metallic braid. For this procedure, use an insulation tester and a connector branch cable. It is commonly used in the industry for acceptance testing prior to energizing the cable and for maintenance testing programs. Cable testing revision 1 june 2, 2011 page 3 of 8 procedures to be used as well as the specifics regarding the cable sample. This guide provides a general overview of the regulatory framework and approval process and explores the specific manufacturing responsibilities and test procedures associated with electrical safety testing. The procedure of insulation resistance test or megger test are given below. In using the megger, a bit of a learning curve is involved.
Connect the opposite end of the test power cable to either outlet of the duplex box. Make sure the circuit is not reenergised whilst the instrument is connected. The client is asking me to do a megger test between core and screenearth to verify the insulation resistance. While cable import and storage are not limited, a maximum of 5 cables can be created using the cable editor of the report edition. I cover the different test methods, an analogy on how insulation testing works, safety and the use of insulation test equipment.
Weve assembled helpful technical guides on insulation testing from leading manufacturers in the field. Five models are available for general purpose testing which. The motor under test must be powered down and disconnected from all equipment and wiring not included in the test. Electrical test equipment cable test equipment megger. A catalogue, for quick reference, of the range of megger test instruments for the maintenance of electrical power systems. Three new pat testers with full database functionality based on the well received pat300 series. User manual megger mpq pq analyzer test equipment depot. The way the connections are made depends on the type of test being undertaken and details are given in measuring techniques. A megger insulation resistance tester is especially useful when you have carried out electrical work on your home and want to make sure you didnt damage insulation or make a wiring mistake.
Transient overvoltage on the supply, which is typically a very brief voltage spike, can be easily simulated and tested by dc withstand test equipment. In many power generation stations, several operational procedures are implemented to utilize the transfer bus as main. The contact resistance test is performed using two current connections for the injection, and two potential leads. Megger insulation tester calibration procedure megger insulation tester is measuring resistance by generating a voltage. The following bite3 data transfer wizard screen shall appear connect the bite3 receiver to the com port you selected, using the null modem rs 232 cable supplied with the unit. Test spikes and long test leads are necessary for all types of earth testing and the optional earth testing field. A significant addition to the comprehensive range of megger low resistance ohmmeters, dlro100 enables low resistance measurement, across multiple applications, in areas without. Insulation resistance testing is a nondestructive test procedure. In this procedure, you check the resistance of system components, drillingdown from string level, through poweroptimizermodule pairs, and finally a single component a power optimizer or a module. The leads used for connecting megger testing with the circuit should be fault free and the two connecting leads should have electrical continuity. For this reason, it is reserved for type tests on new or reconditioned equipment.
Low voltage and high voltage cable testing electrical notes. If physical damage is found, replace the damaged sections. O shortearth the cable conductors momentarily to discharge. A megger test aloone wont tell you much about the dielectric strength of the cable and any world wide reputed company should know this and have also performer a. It is checked by touching the free ends of the leads together while the megger button is pressed on to check for zero. To test a cable with a megger, you connect one probe to the outside of the cable and, with the power turned off, you touch the probe to the conducting wire at the point of connection. Megger regularly audits the performance of distribution partners to ensure they meet standards for technical proficiency and customer support. Power db lite will now display all the data files recorded in the bite3 unit.
This document details powersystems requirements for electrical testing of hv. Insulation testing technical guides megger insulation. This documentation, which can be printed or saved in the form of adobe acrobat pdf files for easy electronic storage and transmission, is an exceptionally useful aid for planning future activities and schedules. The megger company registered the name megger in may 1903 and today offers a wide variety of ir testers. Test methods to be used some test methods cannot be applied to all types of cables. Traction power electrification system investigation wmata. This test will be done on open wire not connected to any devices and is not a motor test. Using ohms law vir, we can compute the value of the resistance. Mar 26, 2017 push the test button of the megger to generate the voltage. Check the value after one minute and record the steady value.
Offering cat iv, the mit1025 is compact, light 10 kv insulation resistance tester for the diagnostic testing and maintenance of high voltage electrical equipment. However, i cant seem to wrap my head around what results i should be looking at. Even though it offers wideranging functionality, powerdb is intuitive in. Test modes the manual test mode allows the user to initiate the test procedure once the probes are in contact with the object under test. The correct settings, connection procedures, test durations and safety precautions must be implemented to avoid damaging the equipment or possible electrocutions. Megger threephase ttr instruction manual pdf download. The fourwire kelvin dc voltage drop is the typical method used by microohmmeters for the contact resistance test, which ensures more accurate measurements by eliminating the own contact resistance and resistance of test leads. A megger is an ohmmeter that measures resistance in the megohm scale.
A cable will be subjected to multiple tests in its lifetime including a series of tests beginning at the factory and potentially continuing throughout the lifespan of the cable. Nexans insulation testing of low voltage cables in the. These conditions result in a decrease in the surfacetosurface contact area with an associated increase in surfacetosurface contact resistance, ultimately causing excessive heating at the junction. The result obtained is a voltage value usually expressed in kilovolts kv. Inspect exposed sections of cables for physical damage. Insulation resistance measurement, however, is nondestructive under normal test conditions. Connect the high voltage test cable to the dc out f post and the ground test cable is connected to ground g post as shown in illustration e. Connect the meggers positive lead to the cable bus wires, shorted together.
Megger products help you install, improve efficiency, reduce cost and extend the life of your or your customers electrical assets. Electrical test equipment power station to plug megger. This document is not part of a manual but it is published to the energy. Threephase ttr measuring instruments pdf manual download.
Megger test procedure manufactured goods electromagnetism. Traction power electrification system investigation report washington metropolitan area transit authority. The group is a global player in the infrastructure, industry, building and local. Megger the complete guide to electrical insulation testing. Pdf format or scanned version of this report may be available and have the status for information only. Readings should be within the specifications provided by the manufacturer.
Each manufacturer is required to comply with the same set of tests according to the same test parameters. It also deteriorates due to the presence of electrical and mechanical stress. Understanding insulation resistance testing pdf 0712 technical assistance 800 34391. After completing a test, capacitive circuits must be completely discharged before disconnecting. Electrical test equipment application solutions from megger. Cable testing revision 1 june 2, 2011 page 2 of 8 cable testing testing represents an integral part in the life of a cable. View and download megger threephase ttr instruction manual online. Carried out by applying a dc voltage with a smaller amplitude. Once the test button is depressed the test lamp will illuminate and the instrument will undertake a single test to verify the resistance of the test object.
Find here insulation testing and continuity, power protection, power transformer testing, power cable infrastructure, cable fault location, general electrical test. Motors are susceptible to the gradual failure of their insulation resistance. In addition, the code clarified the need to record results, determined when a hired item should be included on your register and removed the need to have a retest date on the test label. G safety warnings the circuit under test must be switched off, deenergised, isolated and checked to be safe before insulation test connections are made. The test measures the insulation resistance between the phases andor between phase and ground.
The cable should be tested with at least a 500 vdc megohmmeter megger between the heating cable bus wires and the heating cable metallic braid. Bm12, mj10 mutlivoltage analogue insulation and continuity. Jun 22, 2018 this test may take place on installed or onthereel cable, tools, appliances, transformers, power distribution subsystems, capacitors, motors and any type of electrical equipment or wiring. How does a megger test measure insulation resistance. Im in the case of receiving a new mv 72,5 kv cable at site for installation. That is, with the same test connections and with the same test voltage applied for the same length of time. Test equipment measuring instruments multimeter cable tester circuit tester. The megger technical library provides access to a range of additional content and resources such as technical guides, application notes and more.
Persons not directly associated with the work must be kept away from test activities by suitable barriers, barricades or warnings. The complete guide to electrical insulation testing. The pat 400 series introduces a new level of convenience and speed to pat testing using onboard test results. Following tests are performed for meggering of signalling cable. We have spoken at various points in this manual about the presence of moisture in. Ac voltage test setup and procedure setup for onesecond and sixtysecond ac voltage test methods. The device is being used since 1889, popularity raised during 1920s, since long back devise is same in its uses and purpose of testing, few real improvement appeared in recent years with its design and quality of tester. The first applies to new equipment or cable and can use ac or dc test voltages. The wire itself is usually copper or aluminum, which is known to. Inspect bolted electrical connections for high resistance using one of the following methods. The current version of controlled and reference documents is held. Cable solutions to ensure the reliability of your energy network with energy as the basis of its development, nexans, the worldwide leader in the cable industry, offers an extensive range of cables and cabling systems.
Test instruments for the maintenance of electrical power systems. Electrical insulation testing of hv equipment up to 33kv. I understand what a megger test is, how to do it, and what the purpose of the test is. Complete the steps of the fault location process quickly and safely to minimise downtime for the customer. Threephase dualvoltage motor insulation resistance testing threephase dualvoltage motors are used for most daytoday operations in todays industrial plants. Major megger insulation resistance testers description quality is crafted into every major megger insulation tester, with excellent test voltage regulation, direct measurement readout and an external guard terminal to eliminate surface leakage current from the measurement. Figure 3 echelle typique sur le testeur disolation megger. It is recommended that the test voltage for polymerinsulated heating cables be 2500 vdc or vdc for mi cable. I cover the different test methods, an analogy on how insulation testing works, safety and the use of insulation. Before commencement of any test make sure the surroundings near clear off from any. All other 11kv cable cable installations phase phase and phase earth where. Insulation resistance testing of low voltage cables in the field.
At this time, the software can handle the measurement and test data of the following megger devices. Federal transit administration december 9, 2016 8 new insulators that can be removed for cleaning and then reinstalled. You can trust an authorised megger distributor to help you choose the right test equipment. How to use a megger to measure and test motor insulation. View online or download megger mprt 8430 user manual. Insulation resistance testing of low voltage cables in the. To this end, megger have produced a risk assessment app available on the ios, android and windows platforms. Dielectric testing may be destructive in the event of. The following is a summary of insulation resistance ir testing commonly referred to as megger testing of low voltage cables rated less than 5 kv, recognized by nexans. Sep 26, 2018 a megger is an ohmmeter that measures resistance in the megohm scale. Megger offers cable testing solutions for cable fault location and cable diagnostics, as a packaged cable test van and for telecomdatacom assessment. Dc withstand testing equipment is generally smaller and lighter than an equivalent ac test set.
Cable problems can be generally characterised as local or global e. The vlf test instrument should be solidly grounded before connecting up any cables. Test equipment for a wide range of applications megger designs and manufactures portable electric test equipment. Inspect heating cable and connections for signs of damage. Your complete software solution for managing, analysing and logging measurement data and cable data. These motors run conveyor belts, pumps, fans, and many other applications. Connection setup for a vlf cable connecting a vlf test instrument to a cable refer to ieee 400. With one touch oltc from the ttru3, anyone can configure and test all. Threephase dualvoltage motor insulation resistance testing.
The cable should be tested with at least a 500 vdc megohmmeter megger between the heating cable bus wires and the heating cable metallic. If you are looking for something specific, dont hesitate to contact us. Description and results of the test 1 electrical type tests the cable was subjected to the electrical type tests in accordance with clause. Pat410 perfect for those content to bond test solely at 200 ma, the smallest, lightest of the pat400 series weighs only 2. Insulation resistance quality of an electrical system degrades with time, environmental conditions i. Compare cable data with drawings and specifications. The test set panel must be connected to a reliable local.
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