The importance of transformer tests is all too often underestimated. Yet, the accuracy of transducers has a huge influence on accounting systems. In addition, tests help to significantly reduce the risk of mixing up different instrument transformers or their connections. Tests can also help identify transportation damage inside a transformer. Last but not least, regularly scheduled tests are essential when it comes to detecting effects that can occur within the life cycle of a transformer such as shorted coils, loss of class accuracy due to material changes, or changes to the load. Changing the power supply topology and thereby the primary time constant can lead to a situation where the transformer becomes unusable for protection, as it is saturated far earlier than desired due to transient operations.
The test systems from OMICRON allow highly precise and automatic testing of current transformers as per IEC 60044-1, 60044-6, IEEE C57.13-1993 (R 2003) and IEEE C57.13.6-2005 (ANSI standard) as well as voltage transformers as per IEC 60044-2, IEEE C57.13-1993 (R 2003) and IEEE C57.13.6-2005 (ANSI standard).
Current Transformer Testing
Current transformers are very simple - and yet so complex. A transformer ratio, a magnetization curve and similar can easily be determined. Other parameters, such as unsaturated and saturated inductance or the behavior of a protective core in a short interruption require special measuring processes. OMICRON offers a broad spectrum of options for highly accurate testing of current transformers.
Voltage Transformer Testing
Even with comparatively small voltages and currents, several significant parameters of voltage transformers, such as the transformer ratio or the winding resistance, can be evaluated. In addition, the measurement of the magnetizing current for voltages, even at levels as low as 2 kV, offers interesting information about the status of the transformer. These and numerous other tests can be performed with OMICRON’s CPC 100 universal testing device.
