Testing lab transformer

Transformers for testing facilities

A research lab or a test room need to take into account the most diverse conditions, given by the nature and requirements of the various devices under scope. The standards that regulate the electrical components impose precise conditions at which routine or type tests have to be carried out, imposing a plethora of restrictions regarding the power supply for testing services. The goal for every company is to conform in full to the requests, coming from the standards, that define the tests on the products: this way, both costs and time to market can be reduced, giving benefits to sale prices.

The construction of testing equipment is actually the field for which the customization level is at the highest. The purpose of FDUEG is to manufacture devices which cover all the necessities of a client, possibly with a single product: this has to be characterized by flexibility and adaptability, long service life and the correct price.

The experience FDUEG has in supplying transformers for testing facilities spans for more than 20 years. This includes special requests of heavy current equipment (up to 50 kA impulsively) and voltage insulation reaching 36 kV, in particular to feed power to variable resistive-inductive loads. The typical customers for such a service are companies active in the field of electrical equipment, needing to define their products’ basic electrical properties, but also research and testing labs. FDUEG offers its products for any application that needs a flexible supply for high power rating tests.

The Engineering Department has experience in studying electrical machines to operate tests as per the following international standards: IEC 60070-6, IEC 60070-11, IEC 60070-2 and -5.

Testing lab transformers for testing utilities: tailored solutions and case studies

Testing lab transformer, features

FDUEG keeps a customer-oriented approach to tackle each and every new project for a test room. This starts from the specific requests of clients, to cover a norm’s guidelines and the relative technical specifications. Discussion, analysis of all test aspects and individuation of the most critical conditions are fundamental to design test room transformers.

With respect to the usual power transformers exploited in industry, the special working conditions of a test room require a more precise definition of all critical points related to electrical, thermal and mechanical aspects to attain the most performant compromise.

The transformers of FDUEG are designed for long lasting services and a constant performance. The optimum quality of the magnetic steel sheet and an accurate sizing procedure of the conductors allow for the least possible distortion in the tests’ outcome, in total safety with respect to power supply and delivery for each utilization.

Testing lab transformer, product typologies

A test room transformer has to convey various levels of current and voltage, and rather frequently with large peaks. This obviously must not hamper the safety of the operator and the internal degradation of the equipment.

• Tapped low voltage transformers: they are used to regulate a low voltage upon the load, in order to attain a certain current. FDUEG sets up large regulation interval to cover all the needs in the best possible way, quickly and accurately, without the need for additional regulation steps between supply and load. These devices can also be built as autotransformers.
• Transformers for short circuit tests: these can be built both with medium and low voltage, to sustain high-rate impulsive currents; they typical example of such an application is the service life test for power components.
  Such a device is built with a wide regulation, and is self-limited in current to the rated value in order not to harm any of the appliances in case of net short circuit on the cascaded load.
• Transformers for high current tests and thermal run: this kind of application involves long duties with relatively large currents and low voltage. An example of this is the check, reported in the norms as type transformer test, for the behavior of magnetic power components under thermal stress.
• Transformers for power frequency withstand voltage test: the norm imposes to test the dielectric strength of transformers towards ground, through the application of a single-phase voltage the more or less equals twice the nominal voltage of a certain class. This application usually involves medium or high voltage, needed to reach electric stress large enough to approach the dielectric breakdown voltage of the electrical insulating materials.
• Transformers for partial discharge measurement: they require extreme care in their design phase, since, even if they are built as dry type, on their own they cause partial discharges which end up modifying the test results. Their typical application is related to cast resin winding and insulating oil filled constructions.