Zach Stone, P.E. contacted me after I (Chris Werstiuk writing right now) posted my recent “Understanding the Great Leading vs. Lagging Power Debate” post because I had incorrectly defined
Continue readingI once watched two engineers/technicians argue for two hours about what power definitions should be displayed on a HMI interface. One of them argued that VARs were being EXPORTED during lagging conditions,
Continue readingDid you know that a relay connected to, or set with, the incorrect phase rotation can disable its higher level functions? Did you know that the wrong phase rotation can make your relay testing worthless?
Continue readingIn-service protective relay meter tests are THE MOST important tests that should be performed on every digital relay. All of your offline relay testing is meaningless if: The CT/PT ratios are incorrect. The
Continue readingMeter tests on protected relays connected to open-delta connected PTs can be very confusing. I know I spent a LOT of time trying to figure out the values reported by my first open-delta connected relay
Continue readingUnderstanding phase rotation is vital when connecting two systems together because the results can be catastrophic if someone doesn’t understand how to interpret phase rotation drawings. You would think
Continue readingI’ve noticed that many students don’t seem to have experience with phase angle meters, and they can’t guess what a phase angle meter would measure in simple circuit. This knowledge is CRITICAL if
Continue readingHere’s an excellent video on frequency response in the grid from NERC. I often tell my students that renewables are making the power system less stable and this video explains part of the issue....
Continue readingThe next generation of relay testers need your help! We’re almost finished our “How to Test Protective Relays” Online Seminar and we’re starting to write the next online training
Continue readingI was recently asked about DC Offset during a paper I presented at the 2015 Hands-On Relay School and struggled with an answer because I know what it looks like and I know it exists, but I’ve never heard
Continue readingWaveform diagrams contain every detail of an electrical system, but that information can be difficult to understand without a lot of effort. Phasor drawings take the complex information embedded in waveform
Continue readingWe’re wrapping up our upcoming protective relay online training class: Understanding and Drawing Phasor Diagrams, and we are ready to get started on the next course about the electrical fundamentals
Continue readingSilent Sentinels 1924 Excerpt #6 This excerpt from the 1924 version of Silent Sentinels discusses how electrical engineers calculated short-circuit currents operated in 1924. This is the 6th in the
Continue readingSilent Sentinels 1924 Excerpt #5 This excerpt from the 1924 version of Silent Sentinels discusses how electrical engineers understood how alternating-current systems (AC) operated in 1924. This is the
Continue readingSilent Sentinels 1924 Excerpt #4 This excerpt from the 1924 version of Silent Sentinels discusses how electrical engineers understood how alternating-current systems (AC) operated in 1924. This is the
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