Protection System Scheme Testing
Protection System Scheme Testing
(OP)
I am curious about how folks in the utility world view this. We are a commissioning company and prefer to test for realistic scenarios. Our test protocol (on this job) calls for very simplistic tests.
I feel like we are forced to comply with test specifications that require light bulbs and a flick on an analog meter - and the test is complete.
We have nice test equipment that can easily test a full scheme (inject fault and monitor relay, communications, breaker / reclose, etc).
Our customer seems to think that it is not necessary.
Any comments?
I feel like we are forced to comply with test specifications that require light bulbs and a flick on an analog meter - and the test is complete.
We have nice test equipment that can easily test a full scheme (inject fault and monitor relay, communications, breaker / reclose, etc).
Our customer seems to think that it is not necessary.
Any comments?





RE: Protection System Scheme Testing
Relay tests are not enough. A whole scheme test is necessary. We also test CT's and PT's, as well as all communications paths to the remote ends.
We have from time to time done a syncronized test of protective relays at both ends of transmission lines to find timeing problems with seprate schemes.
Go the extra step. It shows up in reliability.
RE: Protection System Scheme Testing
RE: Protection System Scheme Testing
Coming from an O&M background I probably have a different opinion to many EPC outfits who want the job signed off and handed over to the client while incurring the bare minimum cost and time delay. No offence intended to the good EPC guys who do the job properly.
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RE: Protection System Scheme Testing
1) Functional test, including checking of all mech, key and elec interlocks
2) CT Polarity Test (Flick Test)
3) Primary Current Injection Testing (Include CT Ratio check)
4) VT Ratio check
5) Secondary Injection Testing
6) Hi voltage di-electric test (Flash Test)
7) IR / Megger Test