Currentsensing circuits in test equipment, when available, shall measure only the leakage current associated with the cable under test and shall not include internal leakage of the test equipment. Insulation resistance testing of low voltage cables in the field. Power cables with extruded insulation and their accessories for rated voltages above 30 kv um 36 kv up to 150 kv um 170 kv test methods and requirements cables denergie a isolation extrudee et leurs accessoires pour des tensions assignees superieures a 30 kv um 36 kv et jusqua 150 kv um 170 kv. High voltage dc field testing 52 dc field acceptance testing 52 test limitations 52 test notes 53 maintenance proof testing 53 frequency of tests 53 section 9 miscellaneous information 54 60. An optical time domain reflectometer otdr is the back reflection, portable optical test set used in the field for pre and postconstruction fiber measurements. Cat 6 cable rating that supports up to 1,000 mbs 1gbs data rate. For example, installation method 20 of table 4a2 singlecore or multicore cable on a wooden wall. Knowledge is such a treasure which cannot be stolen. The sensitivity of the test method is limited by contact resistance where the cable sample shield forms a short circuit with the cylindrical test fixture end plate and. Test each conductor individually with all other conductors grounded. Jun 02, 2011 cable testing revision 1 june 2, 2011 page 2 of 8 cable testing testing represents an integral part in the life of a cable.
However, it is important to be aware that there are no industry recognized testing procedures or pd limits for pd tests conducted on complete cable systems. Acceptance test fat, site acceptance tests sat and to ensure quality of the equipmentsystem. Inspect bolted electrical connections for high resistance using one or more of the following methods. 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. This testing of high voltage hv cables manual has been developed for use by. Perform an acceptance test on cables, including terminations and joints, after cable. Cut the cable, insert the componentdevice under test dut and take. Testing of hv cables work shall only be performed by individuals who are appropriately trained, qualified and authorised in accordance with accepted standards within horizon power. Look at the condition of the cable jacket and insulation of exposed sections. Use of a lowresistance ohmmeter in accordance with section 1. The complete guide to electrical insulation testing. Low voltage and high voltage cable testing electrical notes. Whether you test monthly, twice a year, or once a year depends upon the type, location, and importance of the equipment. Vlf testing tan delta loss factor measurement partial discharge.
Din 410212 the cables are mounted with bends on the cable ladder. Regular routine maintenance testing of aged cables has been demonstrated to reduce the chance of unscheduled failure to approximately 10% of the failure rate that might be encountered without such testing. Figure f3 cable feed into cable tray d cable sheaves or a shoe may be used to guide cable into the desired direction, maintain minimum bend radius, and reduce friction. In practice, as you will see in the test methods described below, you. A tool chest of test equipment options should be onhand to ensure a successful and an expedient fault location exercise.
Vlf ac test voltages with cosinerectangular and the sinusoidal wave shapes are most commonly used. The best method to use can vary based on the cable type and construction and the type of cable fault. Reference sheet installation reference method codes. Pd hv and ehv power cable systems neetrac georgia tech. Given below are various kinds of tests that are conducted on cables. Oct 20, 2019 when cable and conductor installations are tested, they should be disconnected from panels and machinery to keep them isolated. Commissioning test for hv underground cable up to 33kv swp sp0407 field instruction sp0407c01 hv cable commissioning test report form sp0407c04 commissioning tool hv cables up to 33kv sp0506. Insure that the input voltage to the test set is regulated. Performed by stressing the insulation of the product far.
Pay attention to the number of sets, the cable size, routing, and insulation ratings. Cable diagnostic tools minimize inservice failures. Low voltage and high voltage cable testing electrical. If the insulation of a cable is free from defects, like water trees, electrical trees, moisture and air pockets, etc. Cable problems can be generally characterized as local or global e. Power cables with extruded insulation and their accessories for rated voltages above 30 kv um 36 kv up to 150 kv um 170 kv test methods and. Test procedure shall be as follows, and the results for each cable test shall be recorded as specified herein. Visual inspection is recommended for all incoming material as cable could be damaged during shipment and delivery. Detailed overview on testing and diagnostic methods and technologies vlf testing. Perform a shieldcontinuity test on each power cable by ohmmeter method. Cable fault location is often more of an art learned from experience than a pure science. Field testing of medium and highvoltage cables may performed for. Iec 60840 power cables with extruded insulation and their accessories for rated voltages above 30 kv um 36 kv up to 150 kv um 170 kv test methods and requirements iec 60228 conductors of insulated cables iec 6028711 electric cables calculation of the current ra ting part 11.
In the past dc has been used on paper lead pilc cables, dc can still be used on pilc cables but only if vlf testing is unavailable. The following tests are type test of electrical power cable. This method is used to energize and to test onsite power cables with sinusoidal ac frequencies. Before moving on to the main hipot testing techniques, it is important to introduce the basic information on power cables, namely their types and typical structure. Pdf type testing of cables and accessories researchgate. Electrical test equipment application solutions from megger.
Cable one or more fibers enclosed in protective coverings and strength members. Other methods for testing fiber optic cable connections include both launch cables and receive cables connected to the power meter. Vlf ac voltage testing methods utilize ac signals at frequencies in the range of 0. Introduction this reference is intended to give a basic overview of insulating materials that can be used during high voltage withstand testing, in particular cable testing. Testing of high voltage cables manual horizon power. Implementation of iec 611961 shielded screening attenuation. Approximately 12% of cables fail during the test and cable repair can then be done in a planned manner. Eiatia 568 calls for a single cable reference, while ofstp14 allows either method.
Visual inspection is recommended for all incoming material as cable. Ac is therefore recommended in most cable testing standards. Understanding insulation resistance testing pdf 0712 technical assistance 800 34391. Testing methods for power cable insulation depend basically on type and material of cable insulation. The conductors should be tested against each other and against ground. Ac high voltage test equipment design vlf operation reduces the power required to load cables which present a capacitive load. Test procedures and test specifications are within ieee and other standards. Electrical utility field testing for mediumvoltage cables. Compare cable data with drawings and specifications. Although cables are tested by the manufacturer before delivery, they maybe damaged while being laid. Cable plant the combination of fiber optic cable sections, connectors and splices forming the optical path between two terminal devices.
Where the cable is fixed to or embedded in a masonry wall the currentcarrying capacity may be higher. Cladding the lower refractive index optical coating over the core of the fiber that traps light into the core. Methods used include arc reflection, simultaneous impulse, impulse current, voltage decay, tdr, bridge, voltage gradient, surge testing thumper, acoustic and magnetic detection, twist method, others etc. Jan 04, 2011 test of simplified fault location method is used for testing. Hvi offers some the most reliable and easy to use tools for assessing cable health in addition to the vlf withstand test. In fact, the vlf cable field tests, based on the standard mentioned before has become a worldwide accepted field test and diagnostic method for commissioning. Megger testing a megger test uses a megohm meter to test the insulation properties of such things as electrical wiring, motor windings and highpower antenna mounts.
Field test procedure for optical fiber link measurements. Voltage withstand simple nonmonitored withstand ability to hold voltage is recorded gonogo test monitored withstand other attributes monitored during test dielectric response or pd temporal stability very low frequency vlf withstand test ieee 400 2012 omnibus. Power cable testing and diagnostics overview testguy. Engineering data for copper and aluminum conductor electrical. Due to the various cable testing methods available, a test method. Minimum resistance readings and specific test methods are determined by acceptance testing specifications for the project. Testing of hv cables supplementary information page 1 of 24 reference sp0407r02 ver 2 ergon energy corporation limited abn 50 087 646 062 1.
Nexans sweden ab, 514 81 grimsas fire resistant cables august 2011 tfn 032580 000, fax 032580320. For this reason, ensuring all connections are extremely clean is an. Cable testing underground cables should be tested before onsite commissioning or recommissioning. Introduction the purpose of this testing manual is to provide guidelines for inspection and testing of various electrical equipmentin compliance to relevant international. The flame retardanceof cables and conductors for fixed routing must be proven in accordance with iec 60332. Submarine cable testing mw90010a coherent otdr by stuart whitehead background with the submarine optical cable industry continuing to grow at a steady rate and the ever increase reliance on transcontinental data traffic, the importance of minimizing optical network downtime has become more critical than ever. Testing methods for power cable insulation abstract. Sp0407r02 testing hv cables supplementary information sp0407r03. Valencia us and international technical service engineer. Buffer a protective plastic coating applied directly to the optical fiber.
Overview of common field tests anixter wire and cable. Sheaves, or a shoe, may be used to guide the cable into the tray. Dnvglst0359 subsea power cables for wind power plants. Tdr time domain reflectometer a method of measuring the distance to opens, shorts or other anomalies on a cable. Test voltages shall not exceed 80 percent of cable manufacturers factory test value or the maximum test voltage in table 100. Timeresistance testing method this method is fairly independent of temperature and often. Vlf cable test voltage ieee standard high voltage inc. The choice of testing techniques and procedures for medium voltage cables is. Cable mounted on a wooden wall so that the gap between the cable and the surface is less than 0. Cable testing revision 1 june 2, 2011 page 2 of 8 cable testing testing represents an integral part in the life of a cable. The most commonly used, commercially available vlf ac voltage test frequency is 0. This test is performed according to a designated test method e.
Testing methods for power cable insulation ieee journals. Inspect exposed sections of cable for physical damage. Electrical utility field testing for mediumvoltage cables this document outlines the various methods for field testing mediumvoltage cable either during or after installation. Except the way the cables are mounted there is only very small diffrences between the testing methods for bbr and din 410212. The failure rate for accessories 33% is higher than for cables 17%. Cut the cable, insert the componentdevice under test dut and take the measurements relative to a baseline measurement of the uncut cable. Inspect exposed sections of cables for physical damage. The hipot test the dielectric voltagewithstand test is commonly known as the hipot test. Pdf because cables and accessories are an important art of the electric infrastructure they are subjected to. You decide which standard you would like to follow. Factory insulation resistance testing is performed when required at the factory of manufacture to ensure conformance to applicable standards specifications.
A dc hipot unit is relatively easy to control, provides accurate leakage current data, and is. Using a vlf unit as the voltage source and a divider to make the measurements, the voltage is raised while measuring the tan delta of the cable. Substation primary plant and secondary systems field testing swp swms001. The system consists of a digitally controlled high voltage power supply to energize capacitive load of power cables. Test methods to be used some test methods cannot be applied to all types of cables. So in this article we use electrical testing of cable systems to show the. Typical conventional power cable insulation is oilimpregnated paper which is used. An optical time domain reflectometer otdr is the back reflection, portable optical test set used in the field. Tan delta, also called loss angle or dissipation factor testing, is a diagnostic method of testing cables to determine the quality of the cable insulation. Designed to verify that the insulation of a product is adequate enough to withstand high voltage. Jun 07, 2011 where hv cable circuits are cut and joined to new circuits, sheath testing must be carried out on the existing old circuit prior to joining to the new cable. Cable testing covers many topics and a broad range of testing methods and equipment, including diagnostic methods of insulation testing such as tan delta assessment and partial discharge detection. Megger guide to electrical insulation testing pdf instrumart. Lan local area network a group of ethernet devices that communicate in a geographical.
However, due to the special construction, application, and hazards involved with higher voltage power cables, the aging and degradation mechanisms, inspection methods, condition monitoring techniques, and controlling. For example, a small pump motor or a short control cable may be vital to a process in your plant. This is the standard test for loss in an installed cable plant and includes the loss measurements at both test cable connection ends. The uncut cable measurement acts as the baseline measurement. Methods for using dc hipot testing of cables were developed in the early 1900s, primarily for testing laminated cable systems such as paper insulated lead covered cable types. Cable testing is often compulsory for laying construction companies and network operators. Record wet and drybulb temperatures or relative humidity and temperature. This test is performed when there is the requirement to take a measurement relative to that of the uncut cable. Crosslinked polyethylene xlpe is now spreading widely for power cable insulation at the rated voltage of 66 to 154 kv worldwide, and especially in japan many 275 kv lines have already been put in service. Insulation resistance testing of low voltage cables in the. The sensitivity of the test method is limited by contact resistance where the cable sample shield forms a short circuit with the cylindrical test.
Vlf is the preferred method for testing all types of cables. Jan 29, 2016 compare cable data with drawings and specifications. Hv test on xlpe cables already in service or previously energized except for new cables, testing at voltage greater than 5. Hipot test is the most common type of electrical safety test. Low voltage cable testing and inspection techniques. System diagram of real test line of hvdc submarine cable test yard.
Then you could begin testing with bad launch cables making all your loss measurements wrong. The test chamber diameter ratio determines the upper frequency test limit, and the length of the cable sample determines the lower frequency limit. Pdf an everincreasing appetite for electrical energy by industrial, commercial. Iec 608853, electrical test methods for electric cables. Iec 6081121 iec 60092359 for shf2 types test duration. Cable test equipment is used to prevent damage to networks and systems and locates faults as precisely and quickly as possible. Engineering data for copper and aluminum conductor. The test method to be used may be one of the following variations. Testing loss there are two methods that are used to measure loss, which we call singleended loss and doubleended loss. A few of the most common test methods are described below. Persulphate test for copper annealing test for copper tensile test for aluminium wrapping test for aluminium conductor resistance test for all test for thickness of insulation for all.
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