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TestGuy is a free online community dedicated to the fine art of power distribution testing, maintenance and troubleshooting. We offer resources to help field technicians gain the knowledge necessary to properly test, assess, and validate electrical equipment.
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This guide provides a basic overview of zone selective interlocking principles and test procedures. Continue Reading
An introduction to transformer winding resistance test methods and procedures. Continue Reading
This guide provides an overview of PPE that may be required for safe electrical work, including insulated gloves, arc flash clothing, insulated tools and other electrical protective equipment. Continue Reading
The selection of a distribution arrangement has a profound impact upon the reliability and maintainability of the electrical system. Continue Reading
Determining the existing condition of power transformers is an essential step in analyzing the risk of failure. Continue Reading
The importance of current transformer tests is often underestimated. CT's for metering purposes must have a high degree of accuracy to ensure accurate billing while those used for protection must... Continue Reading
The field-testing and calibration of solid-state trip units can be performed by either primary current injection method or secondary current injection method. The advantages and disadvantages of each... Continue Reading
Open electrical testing discussion covering all equipment and voltage classes.
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Witnessed an arc flash today...
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Discuss the NETA Level III Certified ETT exam.
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Witnessed an arc flash today on a 1200A distribution panel
I was doing an infrared scan for an electrical contractor on a 120V 1200A distribution board, and as they were closing up the front cover, one of the panel...