Electrical Testing


Transformers are a fundamental part of any electrical system. Transformers allow us to generate, distribute, and utilize power at many different voltages. Power is typically generated at low to medium voltages. It is the transformed utilizing a generator step up transformer(GSU) to a much higher transmission voltage. This transmission voltage allows for sending the power great distances with lower losses than if the generation voltage had been used. At the utility delivery point power is again transformer to a distibution voltage using a power transformer. Power is then distributed to the end user at this voltage at the user site the voltage is typically again transformed to the voltage requirement of the client. This transformer may be a pole, padmount, dry, cast coil, or unit substation type. As you can see even in the simplest scenario transformers are found throughout our electrical power systems so it is important to understand how to commision, trend and maintain transformers in order to reduce hazard to life and property resulting from the failure or malfunction of the transformers in our system.

Acceptance testing and commissioning of new or recently moved transformers is incredibly critical. There are so many factors that can go wrong in the transport ans installation of a transformer all of which can be detected through thourough acceptance testing and commissioning. Many standards have been published on the subject of acceptance testing at AMP we abide by the International Electrical Testing Association and the American National Standards Institute's NETA/ANSI 2009 ATS Standard for acceptance testing specifications.Other useful references may be Institute of Electrical and Electronics Engineers(IEEE), National Fire Protection Agency's NFPA 70B,International Electrotechnical Commission.

Transformer Tests

  • Insulation Resistance
  • Winding Resistance
  • Turns Ratio
  • Power Factor
  • Sweep Frequency