Perform an Acceptance Test

Topic

Perform an Acceptance Test

You want to make sure that all of the physical components inside the relay are functional before you get in too deep. A properly performed acceptance test will make sure that the manufacturer sent you a fully functioning relay.
 

 
Click “Mark Complete” below after watching the video so you can keep track of your progress.

7 Comments
Collapse Comments

Chris,
I may have misunderstood but in the above video there’s mention of checking self check or alarm contact by using Fluke to check continuity ringing when powered down & then when powered up ringing should go away. Is the video suggesting to use continuity function when relay is powered on to see if contact opened? Only ask b/c I’ve always understood to not check for continuity on energized circuit. Thank you in advance

Chris Werstiuk (Administrator) June 4, 2021 at 8:45 am

I agree that a better procedure would be to find out where that contact alarm is connected to in SCADA and make sure that the SCADA alarm actually appears when the relay is de-energized, but that’s usually impractical; so a continuity check is the second best solution.

I also agree that it’s not a good idea to check continuity on an energized circuit (especially an energized trip circuit!), but it is a better solution that lifting wires or de-energizing circuits for a test.

Thanks for the excellent question!

Hi Chris, for the purpose of confirming phase rotation and would you agreed that by simulating/injecting a balanced 3 phase signal to check on pure +ve seq signal (as you proposed) followed by an unbalance signal (phase and magnitude) and check on the phasor diagram/phase value displayed by the relay would also confirm it?

Chris Werstiuk (Administrator) July 25, 2021 at 8:35 am

That method would work also. I probably said in the video that I like to keep things simple and a foolproof as possible, which is why I suggest applying one phase at a time. It’s pretty obvious that if you apply B-Phase voltage or current and you see a C-Phase measurement in the relay. When you apply unbalanced three-phase signals, it’s easier to get fooled into thinking its correct because of unfamiliar color combinations or crappy labelling.

Thanks for the question!

Ha ha ha, makes sense.

abdalrahman sariarah January 28, 2023 at 10:05 am

HI CHRIS
what are the blind spots which the IED self supervision (watch dog, ADC supervision etc.) cant detect it ??

Chris Werstiuk (Administrator) January 28, 2023 at 2:35 pm

Analog Input failure
Digital input failure
Contact Output Failure.

Basically anything interfacing with the outside world 🙂

Leave a Comment