Because transformers are used in a large range of electrical application, testing must be performed on a regular basis in order to ensure that it is functioning correcting and operating to its design specifications.
One of the most common tests performed on transformers is the turns ratio test. With either a step up or step down transformer, it is necessary to evaluate the transformer being used and its application in the field. Many types of testing equipment will evaluate turns ratio (TR), turns ratio by inductance (TRL), low voltage open circuit (LVOC), voltage open circuit (VOC) and voltage open circuit with external sourcing (VOCX).
The simple TR test indicates the actual electrical ratio when energizing the primary winding whereas the TRL reduces the measured turns ratio effect to find an approximation of the physical TR.
While similar to the turn ratio testing, the LVOC gives the actual output voltage while the VOC uses a high voltage and power generator to determine the ratio. The VOCX is for higher capacity testing of power transformers that are above VOC capacities. An external power source provides automatic testing for results.
Vanguard test systems for transformer turns ratio offers single phrase TTR performance to measure ratios from .8 to 15,000. It can be used alone or controlled by computer based on user’s preference. Megger meter systems offers a three phrase TTR for turn ratios on transformers used for power, instrument and distribution, and Doble power factor equipment testing offers transformer turn ratio test equipment as well.
To find the transformer testing equipment you need, contact Protec representatives for a complete inventory list and help with the selection process.