NAIT’s new protection relay textbook is The Relay Testing Handbook!

The Northern Alberta Institute of Alberta’s (NAIT) Electrical Engineering Technology program is a nationally accredited and internationally recognized program that provides a comprehensive study

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The Relay Testing Handbook has been added to the NETA bookstore

The InterNational Electrical Testing Association (NETA) is an organization that serves the electrical testing industry by offering accreditation of third-party electrical testing firms, certifying electrical

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SEL-321 Out-of Step Protection Problem?

SEL 321 OSB upper tests fine, lower is no-op but 51g comes in any ideas? I’m oversight on a project, test company is using a Doble 6150 w/ RTS, I’m not very familair with RTS sdg

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SEL Test Procedure Negative-Sequence Volt-Pol Directional Overcurrent Element

I am writing to enquire about 67N test procedures, specifically Schweitzer relays. The Page 94 of the Relay Testing Handbook #C2 : Practical Relay Testing (50/51/67/59/27/81/87/21) by Chris Werstiuk says

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Real World Problem With an SEL-300G Synch-Check

Here is a story from one of our Customers at Manta Test Systems: “I had to troubleshoot a Schweitzer SEL-300G relay yesterday that had the (25) Sync-Check element enabled, but wouldn’t assert the

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SEL-451 and Frequency Testing Issue

A customer was having problems timing a SEL-451 with a delay setting of 8 cycles. He was measuring a 12 cycle delay when transitioning from 59.5 to 58.5 Hz. If you look at the spec sheet, the SEL-451 frequency

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ASEA RAGEA 27N Gen Neutral Undervoltage

I can not find up dated information on this relay. I am testing with a manta 5000. I put 60 vac 60 hz on leads 7 and 8 and the relay picks up. Then on lead 11 & 12 I put 180 Hz and bring up vac to

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SBF-1 Westinghouse Breaker Failure Relay Failure Question

To all, We had a SBF-1 Breaker Failure Relay fail on us yesterday.  The time delay was not working properly.  We have many of these relays on our system and wanted to see if there has been a Relay Advisory,

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Basler BE1-50BF Breaker Failure Relay Testing

Happy New Year! Does anyone have experience with the Basler BE1-50BF Breaker Failure Relay that has the Control and T1 timer pots and test points on the front of the relay?  There are no timer setting

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Reclose Function

Does anyone have a practical plan for testing the reclose function? I have used amp buckets run through the the breaker to the current input so that the fault current is present as soon as the breaker

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SEL751-A Arc Flash Relay

Does anyone have experience with this relay. More specifically, how are the optical sensors tested during routine maintenance? This looks like a very good relay, but I have concerns about how this unit

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I have a questions about the Phase Differential settings for the GE Multilin SR-489

I have a questions about the Phase Differential settings for the GE Multilin 489 Diff. Trip Min. P.U. is — 0.10 X CT What are they  referring  to the CTR 3200/5 or the Generator Diff. Trip Slope

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Locating fault in the PILOT WIRE between substations

Is there any method to locate the fault in the PILOT wire which normally available in substations? The cross sectional area may be very small about 6 sq mm and is having DC 220- 250 V. Please suggest some

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ABB REL 512

It would appear that everyone is either having no issues with ABB relays or ignoring them in hopes that they will go away. That said, is anyone using a Doble 6150 w/Protest and have good results? nu...

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Testing Siemens 7sj622 Relay’s Directional Overcurrent and Directional Earth Fault Elements

peace be with you all Can you  give me an idea, how to test SIEMENS 7sj622 directional o.c and directional e.f fault relay by using omicron .freja or any Numerical testing instrument? regardes mohammad

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