Partial discharge pd is a phenomenon that has been around for decades and probably was observed in rotating equipment as higher voltages came into use. Test results of surge protection devices shall be in accordance with procedures for testing of lv surge arresters. Each motor is given a routine test as required by bs4999, as59 or nema mg 1 to determine that it is. Large and high voltage motors bespoke construction to your needs engineering the future. Additional special tests beyond the routine test are. Abb offers a full range of high voltage induction motors, including rib cooled motors, modular slipring motors and modular welded frame motors with different cooling options. Compared with other dielectric tests, the differentiating character of partial discharge measurements allows localized weak points of the insulation to be identified. A conveyor motor wont run, the overloads must be faulty. It is a very thorough study of machine condition and life assessment also has fem multistress modelling to achieve highest accuracy of 95 %. Isbn 07389785 ss95211 no part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. Figure 4typical record of insulation resistance of a mill motor. Medium voltage products technical guide protection criteria for medium voltage networks. Commissioning tests for hv underground cables up to 33kv swp page 5 of standard work practice sp0407 ver 16 ergon energy corporation limited abn 50 087 646 062 this test is required for xlpe and paper lead cables. A drain in the air housing protects the motor from damage caused by water leakage.
They interact with each other and cause a gradual spiral of decline in insulation quality. The full load torque of a motor is the torque necessary to produce its rated horsepower at fullload speed. If the surge test fails, the motor condition is critical. Ideal for electricity board and industrial companies for predictive and. Power frequency withstand testing of 38kv switchgear. A good understanding of the application and how to evaluate the motor in. Motor vibration shall be measured in a triaxial direction, i. Introduction to tmeic motors highquality design, manufacturing, and testing excellent motor design tools extensive cad and computerized finite element analysis features highquality manufacturing.
The multistep topology offers low common mode voltage cmv, coupled with the low dvdt, eliminates voltage peaks at the motor terminals. Curve b shows same values corrected to 20c see page 22, giving a definite downward trend toward an unsafe condition. The megger insulation tester is a small, portable instrument that gives you a direct reading of insulation resistance in ohms or megohms. The air housing is in accordance with nema wpii, and features three rightangled turns for air intake, dropping velocity below 3 msec 600 ftmin. Dedicated power and power quality meters for singlephase and threephase frontline power quality troubleshooting with load studies, energy waste analysis and quality of service compliance testing. In recent decades pd was mainly a concern for operators of highvoltage rotating equipment. Understanding insulation resistance testing pdf 0206 rev. Testing 100% routine test quality is emphasised at each step as a motor proceeds through each stage of design, assembly and testing. Distance 250m 500m m 2000m cable size m 11kv or less 400mm2 250 125 60 30 185 240mm2 300 150 75 37. Electric motor testing is usuallly the first thing to be sacrificed when cutting back on operational expenses. Motor horsepower is a relation of motor output speed and torque expressed in lbft.
Inspection, testing and commissioning of electrical. Measured resistance values should be within 50% of each adjacent phase, and comparable to similar. Figure 3typical scale on the megger insulation tester. Hipot test is the most common type of electrical safety. Power frequency withstand testing of 38kv switchgear powell industries, inc. That is, the motor shall not be dismantled to remove sealing elements. Tests results are provided graphically and tabulated. There are five basic causes for insulation degradation.
Inspection and test procedures for rotating machinery. Jul 26, 2016 test current should be equal to the rating of the circuit breaker or 100 amperes. These changes are best detected by conducting a surge and partial discharge test on the motor with a motor analyzer. Electric motor testing explained the electricity forum. The following tests may be performed during routine maintenance and are aimed at assuring. Therefore the xmv660 can be installed with new and existing motors employing standard insulation, without the need for additional motor derating or further motor protection, or to compensate for long motor cables. Therefore the xmv660 can be installed with new and existing motors employing standard insulation, without the need for additional motor derating or further motor. Ieee std 1122004, ieee standard test procedure for. The next generation of distribution transformers lv hv up to 11kv powerstar solo range of super low loss transformers are the only amorphous core transformers designed and manufactured in the uk and provide a costeffective way of reducing energy consumption by upgrading high voltage hv infrastructure up to 11kv. Medium voltage products technical guide protection criteria. This test can be done in your own workshop using simple hand tools and a specialized electric testing device.
Using a test current less than 100a is acceptable, but know that equipment manufacturers usually dont recognize warranty claims based on a 10 ampere dlro test. A wide range of dmms are available to measure voltage, current, and resistance, depending on the motor power ratings. When faced with testing a medium to high voltage motor utilize the secondary circuit to access the current and voltage information. Nema weatherprotected wpiiip24 this motor is designed for outdoor operation. Mediumhigh voltage motor testing note 0303 application note description emax test equipment has a limit of 600 volts, but much of the testing performed is on motors that are operating on 2300 volts or greater. Fluke insulation resistance tester up to 10kv allows testing of high voltage systems such as control gears, engines, generators and cables. Eliminating potential common mode currents cmc from circulating through the motor bearings allows the use of. In a production environment you will soon discover everything is an electrical fault. Induction motor testing and evaluation summary as energy costs rise, more emphasis is being placed on determining the health of large inductive motors. Studies national electric energy testing research and applications center. Ir value for electrical cable and wiring for insulation testing, we need to disconnect from panel or equipment and keep them isolated from power supply. Ir value will be usually high several hundred megaohms for a dry insulation system.
Po box 12818 houston, tx 77217 2005 powell industries, inc. A guide to diagnostic insulation testing above 1 kv 5 what causes insulation to degrade. The most important tests for medium voltage metalenclosed. Rtd circuits shall be in accordance with system design intent and machine protection device. Reverse side of card at right is used to record the test data. Alibaba manufacturer directory suppliers, manufacturers. Electrical insulation testing of hv equipment up to 33kv sub026 issue no. For good insulation, the resistance usually reads in the megohm range. A guide to diagnostic insulation testing above 1 kv. Motor protection relay for high voltage induction motor. However the industry rule of thumb for dc voltage testing is 1.
Home technical articles testing and commissioning procedure for electric motors scope of motor testing it should be noted that the scope of motor testing depends upon the motor type and size, this being indicated on the inspection forms. Ieee std 1122004 revision of ieee std 1121996 ieee standard test procedure for polyphase induction motors and generators sponsor electric. If you have a dc motor that is malfunctioning or drawing and bleeding power through the wires, there are tests that can be done to test the efficacy of the dc motor. Aug 16, 2014 insulation resistance or ir test is carried out by maintenance engineers to ensure the healthiness of the overall insulation system of electrical equipment it reflects the presence or absence of harmful contamination, dirt, moisture, and gross degradation. Testing manual for electrical equipment nahed alhajeri 1and anantha madhavan 2 abstract quality assurance qa refers to a program for the systematic monitoring and evaluation of the various aspects of a project, service, or facility to ensure that standards of quality are being met. Standard for acceptance testing specifications for electrical. Section 7 of the ansineta standard for acceptance testing specifications for electrical power equipment and systems may be reproduced and used on a cut and paste basis for the particular type of equipment to be tested. Hundreds of standards including cable testing standards need for cable testing has existed the 1800s guided ieee 400 series bundle standards ieee cable testing standards. Standard for acceptance testing specifications for. Electrical stress insulation is designed for a particular application. Motor power switching is done automatically by the system. The complete guide to electrical insulation testing. Motor current monitoring and analysis mcsa is a straight forward tool to diagnosing problems with large inductive motors. Partial discharge pd occurs in the stator insulation system of rotating machines, where local electric field stress exceeds the local electrical strength.
Medium voltage products technical guide protection. Jul 06, 2016 if you think im sticking my pinkies in to test the slipring voltage of a 3. In general i have not found a specific bs on the testing of high voltage cables. Sealing elements that can only be removed by dismantling the motor shall be left in place. In most cases, early changes in motor condition will be the first indication that there is a problem. Recommended interpretation of iec 6003421 external contact seals at the drive shaft extension ends shall be removed prior to testing. Routine trip testing should be performed every 3 to 5 years. Partial discharge analysis on rotating machines omicron. The hipot test the dielectric voltagewithstand test is commonly known as the hipot test.
Also speak to a recognised good mv cable test engineers. These contacts are used to break open the closing circuit when the external close signal is removed. For a repair transformer 21 kv is applied on hv side ie 75% of 51 kv. The megger insulation tester is essentially a highrange resistance meter ohmmeter with a builtin directcurrent generator. It can be adjusted to all testing voltages that are specified in ieee 432000. Basics, maintenance, and diagnostics xi contents continued page 9. Its got nothing to do with the tonnes of spillage burying the conveyor and the overloads are doing their job protecting the motor. Learning objectives understanding the hipot test hipot test requirements hipot test considerations and failures arc detection.
Abb has been manufacturing electric motors for more than 125 years and this experience is built in to every abb high voltage induction motor. Oct 14, 2016 11 kv hv cable megger test tamil language. Modern transformers are designed to closer tolerances than transformers in the past. Lowcost portable unit, with all the major motor performance tests of the motorlab system. The following sections of the ansineta standard for acceptance testing specifications for. I used a temporary 433v 3ph supply to the stator which gave 230v between each of the sliprings. Ac pressure test site assembled connections at site. Insulation resistance or ir test is carried out by maintenance engineers to ensure the healthiness of the overall insulation system of electrical equipment it reflects the presence or absence of harmful contamination, dirt, moisture, and gross degradation. Some of the process failures that can be detected by a productionline hipot test include, a transformer wound in such a way that creepage and clearance have been reduced. Timeresistance testing method this method is fairly independent of temperature and often. We offer a wide range of solutions for protective relay testing, primary injection testing, secondary injection testing, transformer testing, circuit breaker testing, resistance measurements, switchgear and electrical panels testing, reclosers testing, iec 61850 testing, substations maintenance, and more. Routine maintenance tests enable personnel to determine if breakers are able to perform their basic circuit protective functions. Test results of motor starter equipment shall be in accordance with. Partial discharge test pd tester electrom instruments.
Such a failure could result from a new operator in the winding department the hipot test a versatile test. Additionally, whilst powerstar solo is an 11kv to 415v amorphous core smart distribution transformer by standard, as a specialist transformer manufacturer with over 20 years experience, powerstar can provide a variety of bespoke solutions including dual voltages, single phase transformers, and three phase transformers. Jul 06, 2016 a dmm digital multimeter, such as this keithley dmm7510 from tektronix, is a musthave instrument for motor testing. You have clicked a page that seems to be very popular. Along with models for advanced power quality and motor analyzers for predictive maintenance. It should be noted that the scope of motor testing depends upon the motor type and size, this being indicated on the inspection forms. This standard specification describes the requirements for the contractor to overhaul ashore in a suitable repair facility an alternating current ac induction or synchronous motor removed from a coast guard vessel. The test voltages for motor andor generator windings are usually the following, where e operating lineline voltage. Motor testing methods based on iec 6003421 p ll determined from residual loss 8.
But, with the introduction of inverter drives used to power electric motors. Inspection, testing and commissioning of electrical switchboards, circuit breakers, protective relays, cables and plcs. Above 90% of motors used in an industry are induction motors, because they are cheap, robust and easy to maintain. Each motor is given a routine test as required by bs4999, as59 or nema mg 1 to determine that it is free from electrical or mechanical defects.
1278 655 366 851 1487 579 243 428 447 316 1116 1219 1043 398 1047 348 1012 706 728 1087 891 1137 431 1314 436 126 514 111 1477 1451 273 709 316 856 459 416 278 817 1496 171 479 70 1107 694 935 878 1406