 |
|
|
|
|
|
|
 |
|
|
|
Published by Megger
Jul 2010 |
|
| The industry's recognised information tool |
|
ELECTRICAL
TESTER |
|
|
|
|
|
|
|
In this issue |
|
|
|
|
Proven Technology |
|
|
The Biddle backstory |
|
|
Putting engineers back in control |
|
|
Electrifying India |
|
|
|
Proven Technology |
|
|
|
|
|
|
|
|
| David Milner |
| Product Manager |
|
 |
|
| Based on the proven technology used in the MCT1600 range of instruments, Megger has launched the MCT1600B. These instruments perform a CT saturation test and calculate the rated knee point at the touch of a button. Tests can be performed at 50 Hz or 60 Hz, and the knee point calculations can be carried in line with IEEE C57.13.1, IEC 60044-1 or IEC 60044-6. |
|
| The MCT1605 and MCT1600B also offer the option of automatically demagnetising the CT under test. Demagnetisation prior to saturation testing helps to ensure that accurate results are obtained, and this procedure is recommended in ANSI C57.13.1. As a further aid to fast, convenient and comprehensive testing of CTs, the test sets incorporate a 500/1000 V insulation resistance test system, which ensures that the CT secondary winding and wiring are properly insulated as required by ANSI C57.13.1. The test set automatically switches the connections to perform all of the required insulation tests, including H-L, H-G, and L-G. |
|
| For maximum user convenience, the MCT1605 and MCT1600B catalogue and store all test results for later retrieval. Configurable test plans can be associated with individual CTs and stored along with the results, which greatly simplifies ongoing monitoring and profiling. |
|
| A particularly versatile option is to transfer the data to Megger’s PowerDB Lite software package, which has powerful facilities for generating reports in industry-standard formats. PowerDB Lite can also be used to control the instruments without the need for operator intervention, thereby allowing them to be used as fully automated computer controlled CT test systems. |
|
| Today’s ever-increasing commercial pressures mean that power engineers now have less time available than ever before for carrying out routine yet essential tasks such as testing CTs. Fortunately, as we’ve seen, the latest CT test sets deliver big time savings complemented by greatly |
|
|
 |
|
| enhanced convenience, thereby providing at least a partial solution to this enduring problem. |
|
| Today’s ever-increasing commercial pressures mean that power engineers now have less time available than ever before for carrying out routine yet essential tasks such as testing CTs. Fortunately, as we’ve seen, the latest CT test sets deliver big time savings complemented by greatly enhanced convenience, thereby providing at least a partial solution to this enduring problem. |
|
|
|
|
|
|
The Biddle backstory |
|
|
|
|
|
|
|
|
| Graeme Thomson |
| VP Americas’ Distribution & Telco |
|
|
|
| A great strength of Megger today is that it builds on the unrivalled expertise of the many innovative businesses that have, over the years, become part of the Megger organisation. One of the most significant of these businesses, particularly in the Americas, is the James G Biddle Company, based in south eastern Pennsylvania. But what is the background of that company, and how did it come to play such an important role in the electrical instrument sector? |
|
| James G Biddle founded his business on George Washington’s birthday – February 22nd – in 1895, after having worked for eight years with James W Queen & Company, at the time a leading manufacturer and importer of high-quality scientific instruments, where he managed the scientific and electrical apparatus department. |
|
| Originally, Biddle described himself as a “manufacturers’ agent” and, from his office in Philadelphia, he corresponded with overseas manufacturers to arrange the importation and sale of scientific and electrical equipment. |
|
| In 1910, Dr. Arthur J. Rowland, head of the electrical department at Philadelphia’s Drexel Institute of Art, Science and Industry – now Drexel University – told Biddle about a new type of device for measuring megohms that represented a major advance over the techniques that were currently being used for testing insulation quality. This was the insulation tester, invented by Sydney Evershed and manufactured in England by Evershed & Vignoles. It was the first instrument that accurately measured the insulation resistance of all types of electrical circuits, machines and equipment. |
|
| As a result of Dr. Rowland’s tip off, Biddle travelled to England, which was no trivial investment of time and money in those days before cheap air travel. There he visited Evershed & Vignoles and, with a gentleman’s handshake, concluded an agreement that made his firm the sole distributor in the USA for Evershed & Vignoles instruments, including Megger insulation testers, Ducter® low resistance testers and earth testers. |
|
| On his return to the USA, Biddle ordered five Megger insulation testers. These he sent out on a sale-or-return basis to some of his closest engineering acquaintances in electrical manufacturing and public utility companies. Four out of the five elected to keep and pay for the instruments they had been sent, providing immediate confirmation that Biddle had made a good business decision in becoming the distributor for Evershed & Vignoles. |
|
| His business expanded and developed, and in 1936 it was incorporated as the James G Biddle Company. In 1940, largely because of his failing eyesight, Biddle retired but in 1945 he was appointed Chairman of the Board. |
|
| As it was impossible to import instruments from England during the years of the Second World War, the company started manufacturing Evershed & Vignoles products under licence in the USA. From that point on the Biddle organisation made products of its own and in 1989, using ideas put forward by the Commonwealth Edison Company of Chicago, |
|
|
 |
|
| James G Biddle |
|
|
| it started development work on a range of instruments for evaluating the condition and performance of large battery systems, such as those used in electrical substations. |
|
| This work ultimately led to the introduction of the BITE (Battery Impedance Test Equipment) range of products. For the first time, these instruments allowed the condition of a battery installation to be accurately assessed without the need for a full discharge test. This concept was so successful that the descendants of the original BITE range are still on sale today, albeit now as Megger products. |
|
| Through the years, the James G. Biddle Company has had a number of other “firsts” in specific types of test equipment that are now standards in the electrical industry. Among these instruments are the first transformer turns ratio test set, the first commercially available cable fault locator, the first partial discharge (corona) detection system and the first automatic 10 kV insulation power factor test set. The descendants of these products still have an important place in the Megger line up. |
|
| In 1991, Biddle and MultiAmp, another major force in the USA test equipment market, came together with Megger to form the organisation that was then known as AVO Megger Instruments. Today, the whole organisation is known as Megger and it continues, as always, to lead the way in innovative test instrumentation that sets the highest standards for performance, usability and value. The company still follows the vision that James G. Biddle used to make his company successful over 100 years ago, “A firm belief in personal relationships, and an intensive desire to perform a special service not elsewhere available.” |
|
|
|
|
|
Putting engineers back in control |
|
|
|
|
|
|
|
|
| GRomain Douib |
| Product Marketing Manager |
|
|
|
| IEC 61850, the new standard for substation data networks, is creating a lot of interest and excitement. It’s also creating more than a few challenges, not least for substation control engineers who spend their lives creating and working on interlocking schemes. And one of the biggest challenges they face is not how to implement interlocking schemes based on IEC 61850, but how to test them. The problem is particularly acute, because at present IEC 61850 is being more widely used for interlocking than it is in protection applications. |
|
| Of course, options do exist for testing IEC 61850 interlocking schemes. However, these almost always involve the use of protective relay test set that supports IEC 61850. This approach, however, is far from ideal. The first concern is that, in most cases, control engineers are not protection engineers. They are unlikely, therefore, to be familiar with the operating a protective relay test set. They could, of course, learn, but that’s a pretty steep learning curve for something that is not central t their work. |
|
| Another issue is that protective relay test sets are necessarily costly, since they incorporate high-performance precision amplifiers and other elements that are expensive to develop and produce. Yet these are not needed for testing interlocking schemes, so using a relay test set in this application is not only overkill, it also needlessly ties up expensive capital equipment. |
|
| It’s clear that there is a pressing need for a reasonably priced instrument that is simple to use and provides all of the facilities needed for testing IEC 61850 interlocking schemes, but does not incorporate the expensive extras needed for protective relay testing. |
|
| It’s not difficult, in principle at least, to imagine how such a test set would work. First of all, it would monitor the GOOSE messages that IEC 61850 installations use to communicate and it would convert them to the ordinary type of on/off binary signal that control engineers are used to working within non-networked installations. |
|
| Of course, there’s rather more to be considered than this very basic overview initially suggests. For example, the conversion between GOOSE messages and binary signals must be fast enough so as not to materially affect the timing of the interlocking system. In practice, a conversion time of less than a millisecond, which is achievable with careful design, will be fast enough to satisfy the most demanding of requirements. |
|
|
 |
|
| Next, it is clearly necessary to be able to associate particular GOOSE messages with specific inputs and outputs on the test set. This is best accomplished with software but, if it is to be intuitive and easy to work with, the software needs to be carefully designed. Further refinements can also be envisaged. For example, LEDs that provide instant visual confirmation of the state of the instruments binary inputs and outputs would be an important benefit for users. |
|
| The ideas mentioned in this article have driven the development of Megger’s new GOOSERTM. This embodies a number of unique technical features for which patents are pending, and offers the most efficient and cost-effective solution currently available to the challenge of testing IEC 61850-based sub-station interlocking schemes. |
|
| That is, however, by no means the limit of the capabilities of the GOOSERTM. While it may not be particularly interesting to control engineers, the unit can also be used to adapt a conventional protection relay test set so that it can be used to test IEC 61850 protection schemes. This is a big benefit for users that already have protection relay test sets – whether they are units supplied by Megger or by others – as it isoffers a very straightforward and cost-effective upgrade path. |
|
| It also creates an attractive option for consultants and smaller organisations who can now purchase a GOOSERTM and a modestly priced relay test set, such as the Megger SVERKER, to cover all of their relay and interlocking test requirements for both conventional and IEC 61850 schemes. |
|
| Equipment that allows convenient and dependable testing of IEC 61850 interlocking schemes has, until now, been difficult or even impossible to find. This situation has now been addressed by Megger’s Goose Message Interface, a unique instrument that provides the added bonus of facilitating the testing of IEC 61850 protection schemes. |
|
|
|
|
|
|
|
Electrifying India |
|
|
|
|
|
|
|
|
| Arvind Shinde |
| Marketing Communications Manager (India) |
|
|
|
| By any measure, India is a big country. It has a population of more than a billion, and a total land area of 3.3 million square kilometres. It’s also a country that’s facing some of the world’s biggest energy challenges. Demand for electrical power, in particular, consistently exceeds the available capacity. In 2008/9, for example, national demand outstripped supply capacity by an average of 9.5%, increasing to 13.8% during peak hours, according to figures from the Indian Power Ministry. |
|
| The situation is exacerbated by the strong growth in the demand for electrical power, which will undoubtedly continue unabated for the foreseeable future. As an example of the many factors driving this growth in demand, it is sobering to note that in August 2009, The Times of London reported that 400 million Indians were without access to mains electricity. |
|
| This situation has led the Government of India (GOI) to set up its ambitious “Power for All” program, one of the aims of which is to increase the country’s generating capacity by almost 80,000 MW between 2007 and 2012. While it is by no means certain that this target will be met, even if only half of the planned increase in capacity is achieved, there will be enormous benefits for all of those involved. |
|
| In a country with a burgeoning economy like that of India, it might be thought that domestic and international investors alike would be keen to play a role in filling the energy gap. Unfortunately, however, things are not that easy. Supply tariffs for some classes of consumer – for example, those in the agricultural sector – are heavily subsidised. |
|
| In effect, this means that the state utilities are obliged to sell power at a loss and they are, therefore, financially weak. As a result, there is little incentive for investors to put money into the building of new power plants that will derive their income from selling power to these utilities. |
|
| India also faces challenges in the field of transmission and distribution. The country is unfortunate in that, for historical reasons, its T&D infrastructure is relatively inefficient. Efforts are being made to improve this situation, but this is no easy task as attempts to satisfy fast growing consumer demand has, in many cases, led to the overloading of key elements like transformers. |
|
| A final challenge for India is finding ways to address its energy shortage while minimising damage to the environment. The country has some of the world’s largest reserves of coal, so the construction of thermal power stations is a tempting option. However, it has been predicted that, unless measures are taken to control present day trends, India will become the world’s third largest emitter of carbon dioxide by 2015, with over 60% of its emissions coming from coal burned in power stations. |
|
| So what is being done to address India’s power sector challenges? The GOI has programs in place to deal with the country’s high T&D losses; these are starting to have beneficial effects and to attract private investment. |
|
| On the power generation front, there is a high level of interest in using renewable resources to supplement the output of conventional power plants. Solar power is a particularly attractive option not only because the tropical location of much of India means that it has the capacity to generate up to 35 MW of solar power per square kilometre, but also because solar installations can be sited in the remote areas where delivering power by means of a conventional transmission system would be difficult and costly. |
|
|
 |
|
| To capitalise on the potential benefits of solar power, late in 2009 India put in place its National Solar Mission, which sets an initial target of 20 GW of solar power capacity by 2020, and calls for a government investment of $19 billion over the 30-year life of the mission. |
|
| The GOI is also taking an increasing interest in nuclear power. The expansion of existing nuclear power stations and the construction of new nuclear plants are both on the agenda, and the plan is for the country to derive 25% of its electricity from nuclear sources by 2050. |
|
| Interestingly, India is outside the Nuclear Non-Proliferation Treaty, which means that it is to a large extent excluded from the international trade in nuclear materials. For this reason and also because the country lacks indigenous uranium, efforts are being concentrated on developing a nuclear fuel cycle based on thorium, of which India has large reserves. |
|
| There are also ongoing developments in the structure of the power industry. For the past ten years, there has been a move to split the state utilities (State Electricity Boards) into individual companies. For example, the former Maharashtra State Electricity Board has been split into the Maharashtra State Power Generation Company Limited, the Maharashtra State Electricity Transmission Company Limited and the Maharashtra State Electricity Distribution Company Limited. |
|
| These three companies now operate independently; they have their own managing directors and they are expected to produce profits. The managing directors have the power to take decisions in the interest of their specific companies, thereby ensuring that they operate smoothly and profitably. Similar changes have already taken place in all of the major states, including Gujurat, Karnatake, Andhra Pradesh, Madhya Pradesh, Orissa and Rajastan. Also in place are incentives for the new private power producers to sell part of the power they generate to nearby industrial users, and the rest to the state power utility. |
|
| To complement improvements in T&D efficiency and increases in generating capacity, India is also making strenuous efforts to ensure that energy is used efficiently. |
|
| In the commercial sector, consumers are being encouraged to adopt variable speed drives for motor control and to downsize motors wherever practicable. In the domestic sector, the emphasis is on switching to high-efficiency refrigerators and using compact fluorescent lamps in place of their incandescent counterparts. |
|
| It has only been possible to mention briefly a few of the many issues that impinge on the generation, distribution and use of electrical energy in India today. Hopefully, however, enough has been said to show that the challenges in this sector, combined with the innate inventiveness for which the country is rightly renowned, are driving the development of innovative solutions that will have benefits far beyond the country’s borders. |
|
|
|
|
|
|
|
News 