How to Perform an In-Service Protective Relay Meter Test

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In-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 relay isn’t connected to its input signals (CTs/PTs). The relay is looking in the wrong direction. The

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How to Perform an In-Service Protective Relay Meter Test

2018 Hands-On Relay School Enrollment Now Open

Want to get the best relay training possible? Sign up for the 35th annual Hands-On Relay School in Pullman, Washington happening March 12-16, 2018. They fill up fast, so you should sign up today! https://cm.wsu.edu/ehome/index.php?eventid=268868& This is not a paid promotion. We did not, and will not, receive any financial

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2018 Hands-On Relay School Enrollment Now Open

How to Perform Dynamic Relay Testing on Digital Relays

The Relay Testing Handbook: Simplified Motor Relay Testing

If you’ve read anything about relay testing written in the last ten years or so, you’ll see a pattern; No-one is talking about the traditional pickup and timing tests most relay testers (and most automated relay testing software) use to test relays. You are much more likely to read terms

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How to Perform Dynamic Relay Testing on Digital Relays

Why Does My Open-Delta Connected Phasor Diagram Look Weird?

Meter 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 during my first simple meter test.  The voltage and current phasors were completely out of

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Why Does My Open-Delta Connected Phasor Diagram Look Weird?

Why Do Traditional Line Distance Protection Relay Testing Procedures FAIL on Digital Relays?

Traditional line distance relay testing procedures (MTA, Reach, and Timing) are a great way to test electro-mechanical relays and learn how line impedance relays operate; but they are inefficient, ineffective, and frustrating when applied to modern digital relays. This post will show you why your traditional tests are probably failing,

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Why Do Traditional Line Distance Protection Relay Testing Procedures FAIL on Digital Relays?

Overcurrent Relay Testing Online Seminar – Under Construction

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We need your help with our next online seminar about overcurrent relay testing. What would you like to see in an online seminar about overcurrent relays? Our current rough outline includes: Why Do We Use Overcurrent Protection? Introduction to Fault Studies Calculating Maximum Current With an Infinite Buss Introduction to

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Overcurrent Relay Testing Online Seminar – Under Construction