It was a bad aux relay. But was intermittent, so it made it difficult.
All linkage and mechanisms were tight and properly connected.
Thx for your insights.
OT2020
While performing routine timing tests on a 15kv 1200 amp OCB, bot the close command test data and the open command test data was well within trending perimeters. But when performing a close/open command, ( simulating closing into a fault), all data came back 000.000 on ALL poles, and on both...
Looking for some seasoned advice on choosing a single conductor cable for a DC replacement project.
Cable will be 2/0 copper, will be in out door cable trench( exposed to weather) in conduit ( separate) , and also run inside in cable tray.
I have checked a few vendors ( Okonite etc)...And I...
Recently on our 72K Dead Tank( Alstom) SF6 CB's, we have been getting a rash of negative readings. We perform GST, GST (guard) and UST tests.
Some of our tests are coming back negative Pf, and negative watts. This has happened a couple of times in the past, and when tested a year later, the...
"I'm not sure why you expect to see recent construction. The SPCC rule may have been modified recently, but it has been around for a while now; and containment or equivalent was considered good engineering practice prior to that.
Containment is generally underground, and not very visible from...
I have searched for like threads, but have not found anything current.
Based on the current CFR Title 40 dated February 12, 2012, if a transformer of sufficient size is located in an area that is miles from a navigable water source ( city area), would a SPCC still be sufficient?
The document...
Thank you Waross and Pwrengrds.
I agree that the pad are in an odd place. But they are factory installed, they came right from Cooper The portion that looks rusted is actually just the paint peeled back because of the heat.
We should hear back from Cooper tommorow morning. A contact at...
Here is also a picture showing these pads between the bushings.http://files.engineering.com/getfile.aspx?folder=954f7a31-37b9-4a92-b51e-12e947def89c&file=IMG_0527.jpg
Recently we received quite a few Cooper 997kva 7200-277 single phase transformers, for use in some of our larger customer subs. Some have been installed, and when IR scanned, they show excessive heat( 300f) right between the secondary bushings. In this exact area between the bushings, and on...
We don't as a rule document the ambient temp of the day, while sampling. I guess we should.
Then again, the outside testing company didn't document that as well.
But I'm sure, with some researching, and knowing the dates all samples were taken, I could probably get that info off the net for...
Recently a 15mva transformer at one of our small substations was sampled for DGA.
Our sample showed 6ppm for moisture in oil(D-1533B) and 7ppm for % saturation at top oil temp. The interfacial tension was 39.8
One week BEFORE, an outside testing company, using the same testing lab, sampled...
